The enemy never quite knew where the Allied landings in North Africa, Sicily and Italy would take place. It is true that our plans for these operations had been based on the information from ULTRA as to where there would be least opposition, but if for a moment one reverses the roles of ULTRA there would have been little chance of our amphibious invasions in the Mediterranean or in Normandy achieving the successes they did. It is, I think, true to say that on these counts ULTRA was the vital factor.i.
The middle phase of the war against the Axis powers was fought in the Mediterranean – in North Africa, Malta, Sicily, Italy, Greece and the Balkans. In this theatre of conflict, as in the others, the information provided by Bletchley was crucial in bringing victory. The Allies faced two highly gifted opponents, Rommel in North Africa and Kesselring in Italy, either of whom could have defeated them, and the edge given by access to the German commanders’ thoughts enabled the Anglo-American commanders to exploit their own strengths and their enemies’ weaknesses.
The Mediterranean might seem an unlikely or even unnecessary place in which to conduct a war between Germany and the Allies, but certain factors gave this region strategic importance. First, Germany’s co-belligerent, Italy, was a dominant power in the region. The Italians boastfully called the Mediterranean ‘Mare Nostra’ – ‘our sea’ – and had colonized several parts of it: Libya, Tripoli and the Dodecanese. Other Italian territories – Somaliland and recently conquered Ethiopia – posed a threat to East Africa and the Persian Gulf. Britain too had possessions, or mandated territories, in the area: Gibraltar, Malta, Cyprus, Palestine and Egypt.
Second, the Mediterranean was the key to the Suez Canal, and the canal was the key to India and the Far East. Even more importantly, the oil fields of Iraq were vital to Britain’s war effort. Mussolini wanted a share in the glory that he expected the war would bring, and it could be assumed that he would attempt to seize British territory if opportunity offered. In any case he decided to conquer his neighbours and attacked Albania, forcing its king into exile. He found himself opposed by tough Greek armies and became bogged down in the mountainous terrain through the winter of 1940–41. Italian efforts were proving inadequate, and Mussolini (who had acted without Hitler’s support) was saved from disaster and humiliation only by the arrival of German armies to assist him. They went on to invade Greece itself. Britain assisted by defeating the Italian navy at Taranto in November and by sending its own troops to the aid of the Greeks. The Balkans became the scene of some of the war’s most bitter fighting.
The defeat of France had led to the creation of the collaborationist Vichy Government, and French colonies in North Africa (Algeria and Morocco) became enemy territory. When Vichy refused to hand over to Britain its Mediterranean fleet, which was in port at Mers-el-Kebir, the ships were shelled and sunk by the Royal Navy on Churchill’s orders, to prevent their use by the Axis.
With Western Europe in a state of impasse, the Mediterranean was thus growing into a major theatre of conflict and a natural arena for the contest between the Axis and the British Commonwealth – for troops from India, Australia, New Zealand and South Africa fought alongside the British. The region’s importance could be gauged by the fact that in July 1940, with invasion of southern England a stark possibility, the government despatched to North Africa the only significant number of tanks it possessed that had not been abandoned at Dunkirk.
There they were put to good use. The loss of face caused by the British Army’s retreat from France was avenged to some extent by success against the Italians. At the end of 1940 the British, commanded by General Richard O’Connor, broke through the Italian lines at Sidi Barrani, surrounded a large enemy force and took 38,000 prisoners. During the next few months the Italians were driven out of Egypt and Cyrenaica. These victories on land were matched by a decisive success at sea, when Admiral Andrew Cunningham’s Mediterranean fleet delivered a crippling blow at Cape Matapan, off the southern tip of Greece, in March 1941. Cunningham had his headquarters in Alexandria and he and his officers had been under close observation by the Japanese consul there, who was a member of the same club. Aware, from the reading of Axis code messages, that his movements would be reported to the Italians, Cunningham deliberately allowed himself to be seen relaxing there on the Friday before the battle and was heard loudly making arrangements to play tennis the following day. After dark, however, he and his fleet sailed quietly out of harbour and caught the Italians entirely by surprise. This was to be the last occasion on which the Italian surface fleet was brought to battle.
Cunningham had known exactly where to find his opponents – as well as their number and firepower, and even the fuel situation of their ships – because of the work of the Station X codebreakers, who had been listening to the signals traffic of the enemy fleet. Bletchley housed an Italian section, whose codebreakers had found this enemy’s ciphers easier to read than those of the Germans. It was to score numerous successes during the Mediterranean war, but perhaps Matapan was its greatest triumph.
Getting such information to commanders in distant fields of conflict was problematic. To protect the secrecy of its source, the smallest possible number of people must see the messages or know of their existence. They were therefore too sensitive to send abroad through even the normal secure channels, and at the receiving end could not be trusted to the eyes of secretaries or adjutants. The solution was that Bletchley sent its own representatives to the theatres of operations. These security-vetted specialists, rather than ordinary army signallers, received the messages sent from Station X and ensured that they reached their destination. This meant the establishment of small units that accompanied the armies in the field. There must in each case be several men for they, like their counterparts at Bletchley, would need to work round the clock in shifts, and might, of course, expect to suffer casualties. Though they shared the discomforts of their comrades, sleeping in slit trenches or jolting in convoys along dusty roads, they were self-sufficient. Operating their radios from tents or the backs of vehicles, they would receive the information in code and write it out for delivery to the recipient. No one else, no matter how exalted in rank, would be permitted so much as a glance at it. These groups of operatives – the link between the huts of Bletchley Park and the battlefields on which the results of their work were put to use – were the Special Liaison Units, or SLUs. They were set up and controlled by Group Captain Winterbotham. They derived their information from another close-knit communications group, the Special Communications Unit (SCU). The latter, according to RT Jenks, had a comprehensive array of functions:
Duties of SCUs ranged from interception of enemy traffic, direction finding, mobile D/F and location of enemy agents in the UK and abroad, relaying of traffic across the world, operation of deception traffic, supervision of turned agents, co-operation with clandestine units overseas, to handling of the traffic for SLUs.
SCU 1 was formed about August 1941 above the Passport Office in Petty France (a street in London). It later moved to the Bletchley complex. It is thought to have been formed initially from a mixture of RSS and ‘Y’ service personnel. It was the ‘mother hen’ of the organization, supplying staff for other SCUs.
The origins and organization of the SLUs have been described by army signaller RT Jenks, who served in one:
The Special Liaison Units were masterminded by Group Captain Fred Winterbotham. The German Enigma and other traffic intercepted by SCU 3 was decrypted at Bletchley Park. The vital traffic intended for German commanders in the field was given the code name ULTRA, and was sent immediately, after receiving by one-time pads or Typex machines, from Windy Ridge by SCU operators to the appropriate SCU/SLU in the field. The SCU operator received the traffic and handed it to the SLU (RF cipher sergeants and officers) who decoded it and passed it to the Allied General Staff Officer. An apocryphal story, which could well have been true, tells of a message which due to poor radio conditions and/or poor German operating had to be repeated innumerable times. The SCU intercept operator, however, took a solid copy first time and the traffic was passed as above, with the result that the Allied General knew the orders before his German counterpart.
Within an SLU there could be several groups, each serving a particular command in that area, Army, Navy, Air Force, British and US. A group usually consisted of 3–6 SCU operators, drivers and up to six RAF cipher sergeants with an RAF officer. The CO varied as to who the group served, British or US, Army or Air Force. Groups might be combined for a time and then split up as required. Each group was usually given a code name, e.g. CROWN, HANS. Not all SLUs had radio links, but were supplied with their information by teleprinter or dispatch rider.
Initially ‘one time’ pads were used for encryption but the Typex machine became available later in 1942.
The units served all over the world and at every stage of the conflict:
Most of the radio links worked direct to Windy Ridge [Whaddon] but some worked through relay stations in India, Egypt and Morocco. Some SLUs are reported as having travelled with Churchill to conferences, e.g. USA, Casablanca, Teheran, Yalta.
There was an SLU of a sort with Lord Gort in France (1939/40) and also at Meaux (Paris) with Air Vice Marshal Barratt. They evacuated via Brest at the time of Dunkirk (May 1940).
There was an SLU at Fighter Command (Stanmore) working by teleprinter to Bletchley at the time of Operation SEA LION (the proposed invasion of Britain) and the Battle of Britain (Operation ADLER, August 13 – September 15 1940). An SLU in Cairo served General Alexander and later General Montgomery (8th Army) and Air Marshal Cunningham (Desert Air Force), with an extension to Alexandria for Admirals Ramsay and Cunningham. An SLU in Malta served all three services.
Personnel for SLU 9 went by sea to Canada and USA, then by train and flew to Australia. HQ for SLU 9 was in the A.M.P. Building in Brisbane and it appears that they became members of the Royal Australian Air Force. There were groups in Laye (New Guinea) for Australian 1st Army and RAAF, Manila for General MacArthur, Morotai in the Moluccas and Laubaun Island (Borneo) for 1st Tactical Air Force, RAAF. A group was due to move from Borneo to Manila when the atom bomb was dropped on Japan and the move was aborted. Information from London and US went to Brisbane by cable and radio.
In 1943 an SLU, and presumably associated SCU, was provided for C in C India at Delhi, and another for General Slim, C in C 14th Army at Comilla in Assam. About September 1944 an SLU was provided for Admiral Mountbatten (SEAC) at Kandy in Ceylon. These SLUs also provided service to US Army and Air Force in China with Chang Kai Shek. Information to them came from London, Brisbane and Washington.
The men (for this aspect of the communications war was an entirely male preserve) recruited for work in SLUs were already serving in the Forces as signals specialists. They were otherwise a disparate bunch. Most had undertaken, or would be sent to complete, the necessary crash courses to bring their knowledge and abilities to a suitable level. They were summoned, as needed, from all manner of different places and postings. They were interviewed and then trained in London, living in hostels and receiving instruction in converted private houses or, more intriguingly, in commandeered national museums (rooms in two of the great treasure houses of South Kensington, the Victoria and Albert and its neighbour the Natural History Museum, were used for this purpose). Most were puzzled to receive a summons to London that gave no indication as to why they were wanted. All of them recall the sense of excitement at the job they were to do, and the continuous emphasis on the penalties for divulging anything of what they knew. Squadron Leader Oliver Reece described his experience:
After two weeks at the officers’ training school at Wolverhampton, designed to convert Erks like me to officers and gentlemen, I was summoned to an interview at Air Ministry to determine if I were fit for an intelligence commission, for which I originally applied, in the belief that my knowledge of Spanish and French might be useful. They sent me to Highgate for a crash intelligence course for two weeks, mostly devoted to aircraft recognition and security.
From there I was sent for an interview at Victoria Street at which I met Wing Commander (Tubby) Long. He asked me if I was willing to go overseas and I told him I would have to go wherever they sent me. He emphasised that he could not tell me where and he came on strongly about security and secrecy. So that was my entry to SLU.
Next came a crash course in coding with one-time pad, taken at a boarded-up house near Sloane Square, inside which was a multi-lingual hive of agents in training. My instructor was Squadron Leader Macdonald, a university French professor.
Sergeant Frank Brailsford’s training had been a combination of square-bashing and cipher work:
I joined the RAF and served in the RAF Regiment until the spring of 1943. An IQ test was then carried out to select personnel who were capable of doing a different type of duty, and I was selected to become a clerk c.c. [Clerk and Cipher]. After passing the drill course at Cardington I took a code and cipher course at Oxford. I found the work most absorbing and at the end of the course we had a final lecture from a senior RAF officer about the absolute necessity for complete secrecy in dealing with cipher work of any kind. To emphasise this point he concluded by quoting a biblical verse from the first epistle to Timothy, chapter 6, verse 20, which reads: ‘O Timothy, keep that which is committed to thy trust, avoiding profane and vain babblings and oppositions of science falsely so called.’
From Oxford I was posted to a cipher office at RAF Annan where I spent the autumn and winter of 1943–4. In the spring of 1944 I was posted to SLU 8 and commenced by attending the cipher school in Hamilton Terrace, north London, to learn the mysteries of the Typex cipher machine and to be told of the Ultra secret intelligence.
Josh Reynolds had also done all the right courses:
For me, one of the most fascinating jobs of World War II started after I had passed through the normal RAF Code and Cipher School known as No. 5 Radio School, Oxford, and was waiting at Winslow for posting overseas.
Flight Lieutenant Gibson, whom I later learned was one of the four original RAF officers recruited by Group Captain Winterbotham for the Ultra Intelligence team in Hut 3 at Bletchley, came down to select cipher sergeants for the Special Liaison Units in North Africa. I was, I think, picked because I knew German, and together with several others was then sent off on leave only to find we were being very thoroughly checked on by our local police for every aspect of security. It was an odd experience since we didn’t know at that time what we were going to do. Anyway, I seemed to pass the test because I then reported to London and about eight of us did the special course in ‘one-time-pad’ and also on the new Type X cipher machine, and it was here that Group Captain Winterbotham indoctrinated us in the mysteries of ‘Ultra’, and suddenly the war had come alive. We were to be right at the centre of the whole business.
Every morning a black Foreign Office van [with an] armed guard brought to our empty house in Sloane Square locked and sealed boxes and cases with the machine and books and Ultra material and each night it was taken away again. It was my first lesson in security. There was a Squadron Leader Long who taught us all that we should have to do in the field, and reiterated the warning that if ever the enemy were given any cause to suspect we were reading their most secret signals, Ultra would cease, and with it a large part of our chances of winning the war. There was a nice touch too when we were warned that if there was any leakage of the secret to anyone who was not entitled to know it, the guilty man would be shot. We very soon realized why such care had been taken in our selection and security checks. There was a strangely close-knit companionship between all the men I was to meet in the various Special Liaison Units in which I served, for we could never mix with other units of either service. It was at first a rather difficult situation but I think it made us all the more self-reliant.
One other thing we all had to learn was a thorough maintenance course on the Type X cipher machine. I suppose the RAF who designed this cipher machine had learned what to avoid after we had succeeded in breaking the supposedly unbreakable German Enigma [code]. We had to be able to keep our Type X in top working order under all conditions.
It gave our morale a tremendous boost to feel we were considered so important despite the fact that we were only sergeants, and the signing of the Official Secrets Act was to us a significant moment.
Sergeant Jack Mellor found difficulty in attending the interview:
I remember when I first reported to Hamilton Terrace for the special cipher course, prior to being posted to SLU 8 at Bushey Park, I was met by an army officer, I think it was Lieutenant Colonel Gore-Browne, who – patting an enormous Smith & Wesson revolver on his hip – said he would shoot me with his own hand if ever I revealed the secrets I was about to learn.
My reporting to Hamilton Terrace did, in itself, have a funny side. Due to an error in the transmission of the signal to my Coastal Command station at Beaulieu in the New Forest, where I was working as a cipher clerk, my instructions read to report to ‘8 Hamilton Terrace.’ I duly arrived at No. 8 only to find that it was a completely empty and deserted house. This was a bit of a puzzler, I remember thinking ‘By God this IS a secret outfit!’ Using a bit of initiative which I didn’t know I had I tried No 18, much to the surprise of the civilian residents, and then No 88. So commenced my career with SLU 8.
Commonwealth forces attacked the eastern Italian colonies and, despite sporadic but spirited resistance, had taken control of Ethiopia and Somalia by the end of 1940. These victories were helpful in protecting the Suez Canal, but were otherwise of no great significance, because while the Allies had captured vast areas of enemy territory in East Africa, they had lost a more important conflict farther north. The Allies had been driven out of Greece by Axis armies (despite a warning from Ultra that German forces were building up in Romania to strike) and after fighting a rearguard action were forced to withdraw to Crete in what seemed a weary repetition of Dunkirk. According to Anthony Beevor’s book, Crete: The Battle and the Resistance, a signal from Bletchley on 22 April 1941 to the British Legation in Athens requested urgently the destruction of Ultra signals:
Take greatest care to burn all deciphered material this series. Vital security our source.
On Crete a force of British and Commonwealth troops, commanded by the New Zealander General Bernard Freyberg, dug in. Though it was expected that the island would in turn be invaded, his men had adequate time to prepare. The defence of Crete was the first occasion on which Ultra intelligence made a significant difference to a major land battle. Thanks largely to the laxity of the Luftwaffe in observing security procedures when signalling with Enigma, eavesdroppers in Bletchley’s Hut 3 had gained an immense amount of detail about the enemy’s organization, supplies and, most crucially, mode of transport, and this was relayed to Crete from Allied Headquarters in Cairo. The Germans had the option of a seaborne invasion or an airborne assault. For the defenders it was vital to know whether to spread their resources around the coasts to repel landings, or to concentrate them on plains inland to prevent paratroops from seizing the heart of the island. Ultra made available to Freyberg information so comprehensive that the enemy attack could have been decisively crushed had it been taken at face value.
This type of signal would be handed to commanders by their SLU officers throughout the rest of the war. Summarizing the results of many hours’ interception, decrypting and translation by a team of experts, these slips of paper must have seemed, to those with the responsibility for making weighty tactical decisions, like a gift from heaven. It is worth examining one of these messages in detail, as quoted by Beevor, because (despite some inaccuracies in the figures) it demonstrates the depth of knowledge, and thus the scale of the advantage, that was given to the Allies by Ultra:
OL 2/302 1745 hours 13.5.41
The following summarises intentions against Crete from operation orders issued.
Para 1. The island of Crete will be captured by the 11th Air Corps and the 7th Air Division and the operation will be under the control of the 11th Air Corps.
Para 2. All preparations, including the assembly of transport aircraft, fighter aircraft, and dive bombing aircraft, as well as of troops to be carried both by air and sea transport, will be completed on 17th may.
Para 3. Transport of seaborne troops will be in co-operation with admiral southeast, who will ensure the protection of German and Italian transport vessels (about twelve ships) by Italian light naval forces. These troops will come under the orders of the 11th Air Corps immediately on their landing in Crete.
Para 4. A sharp attack by bomber and heavy fighter units to deal with the allied air forces on the ground as well as with their anti-aircraft defences and military camps, will precede the operation.
Para 5. The following operations will be carried out as from day one. The 7th Air Division will make a parachute landing and seize Maleme, Candia and Retimo. Secondly, dive bombers and fighters (about 100 of each type) will move by air to Maleme and Candia. Thirdly, air landing of 11th Air Corps, including corps headquarters and elements of the Army placed under its command probably including the 22nd Division. Fourthly, arrival of the seaborne contingent consisting of anti-aircraft batteries as well as more troops and supplies.
Para 6. In addition the 12th Army will allot three mountain regiments as instructed. Further elements consisting of motor-cyclists, armoured units, anti-tank units, anti-aircraft units will also be allotted.
Para 7. Depending on the intelligence which is now awaited, also as the result of air reconnaissance, the aerodrome at Kastelli south east of Candia and the district west and south west of Canea will be specially dealt with, in which case separate instructions will be included in detailed operation orders.
Para 8. Transport aircraft, of which a sufficient number – about 600 – will be allotted for this operation, will be assembled on aerodromes in the Athens area. The first sortie will probably carry parachute troops only. Further sorties will be concerned with the transport of the air landing contingent, equipment and supplies, and will probably include aircraft towing gliders.
Para 9. With a view to providing fighter protection for the operations, the possibility of establishing a fighter base at Skarpanto will be examined.
Para 10. The Quartermaster General’s branch will ensure that adequate fuel supplies for the whole operation are available in the Athens area in good time, and an Italian tanker will be arriving at Piraeas before May 17th. This tanker will probably also be available to transport fuel supplies to Crete. In assembling supplies and equipment for the invading force it will be borne in mind that it will consist of some 30 to 35,000 men, of which some 12,000 will be the parachute landing contingent, and 10,000 will be transported by sea. The strength of the long range bomber and heavy fighter force which will prepare the invasion by attacking before day one will be of approximately 150 long range bombers and 100 heavy fighters.
Para 11. Orders have been issued that Suda Bay is not to be mined, nor will Cretan aerodromes be destroyed, so as not to interfere with the operations intended.
Para 12. Plottings prepared from air photographs of Crete on one over ten thousand scale will be issued to units participating in this operation.
Unfortunately, the army was not yet accustomed to working with Ultra. Freyberg could not be told the source of the information (presented as the result of espionage) so could not be expected to accept its accuracy entirely. He did not study some of the signals and did not entirely understand others. He had made up his mind that an attack by sea was the most likely situation, and he shaped whatever Ultra intelligence he was shown to fit his expectations. His troops were placed in coastal defence positions.
On 16 May, an Ultra signal gave him even more information about the enemy’s intentions. Another message announced:
OL 10/341 0155 hours 16.5.41
From further information postponement day one for operation against Colorado (Crete) confirmed. 19th May seems earliest date.
It was on 20 May that German parachutes began to open in the skies above Crete. Allied defence was spirited, but much manpower and energy had been wasted on the coasts when the enemy’s clearly stated objectives were inland airfields. The defenders had no chance of seizing the initiative, though the attackers suffered heavy casualties. Given the enemy’s superiority in numbers and equipment, the outcome could not be in doubt and in a matter of days they had overrun the island. Allied survivors retreated to the south coast where, thanks to the Royal Navy, they were evacuated from Greek territory for a second time. Winterbotham later suggested that, despite the defeat, disaster had been averted:
In Crete ULTRA denied surprise to [General] Student’s parachute invasion and, although the island was lost, our knowledge undoubtedly saved most of our forces from capture.
Also significant was the fact that the island would have proved very difficult to hold, requiring a garrison of several divisions that could not have been spared from fighting elsewhere. In the event it was the Germans who had to provide a garrison, depriving them of much-needed manpower.
In North Africa, Hitler had decided to intervene and rescue the Italians from further debacle. He sent Erwin Rommel, a gifted commander whose tanks had helped to win the Battle of France, with a German ‘Afrika Korps’ to reverse the tide of Allied successes, and Rommel did so almost at once. He found Commonwealth troops entirely unprepared. Their commanders assumed that, with the vanquishing of the Italians, enemy forces in Africa had been defeated and, with worries elsewhere (it was necessary to suppress a revolt in Iraq), many experienced soldiers had been moved out of the area. Rommel’s Afrika Korps swept westward, wiping out earlier Allied gains (with the exception of Tobruk, which was besieged) and heading for Egypt.
The Allied Eighth Army began at once to counterattack. ‘Operation Crusader’ was a trek westward to raise the siege of Tobruk, and after heavy fighting it succeeded. The war then ranged back and forth across the desert, with both sides advancing or retreating according to their fortunes. In the first half of 1942, Rommel scored a series of successes that included the capture of Tobruk. The defence of this city during the previous year had been presented to the world as an epic of heroism; its loss was thus a propaganda triumph for the Axis. The fall of Tobruk, which was no longer of great strategic importance, was one of the most important landmarks in the desert war. The Allies were pushed eastward to the Egyptian border, and preparations were made to evacuate Cairo. Rommel was promoted to Field Marshal.
He and his men may have savoured this triumph, but this time it was the Afrika Korps whose fortunes were about to turn. A few months later, in July, his forces were stopped at El Alamein, an insignificant railway junction in the desert, by a combination of well-prepared Allied defences and the sheer exhaustion of his soldiers. He paused, for the moment, to gather strength for the next stage of his march to Cairo. FW Winterbotham commented that:
During the long fighting withdrawal of our Middle East forces from El Agheila back to Egypt, pressed all the way by the relentless Rommel, it is doubtful whether, without ULTRA, Wavell or Auchinleck (successively Commander-in-Chief Middle East) could have so cleverly boxed him to a standstill.
Thanks to Ultra information relayed by the SLU attached to Auchinleck’s headquarters, the Allies had known a great deal about Rommel’s intentions. Bletchley had read the communications between the ‘Desert Fox’ and Hitler but, tragically for the Eighth Army, it was not only the British who had access to the details of the enemy’s plans. A well-placed source in the Allied camp was unwittingly providing German Intelligence with a continuing stream of information. Britain was anxious to bring the United States into the war, and the American military attaché in Cairo was given access to battlefronts and to highly classified material in order to influence him favourably. He was naturally reporting his impressions to Washington. He did this in considerable detail, using the State Department’s Black Code. Historian Barrie Pitt described the circumstances:
The Axis powers had broken the American State Department cipher by which its military representatives reported from the field. Since early 1941 one such representative – Colonel Bonner Fellers – had been in Cairo, and his genuine sympathy with the British cause had so impressed Middle East HQ that he had been allowed to witness the whole of the Crusader operation from whatever vantage point he requested, and after Pearl Harbor was admitted to the innermost circles at GHQ.
As such, he attended General Auchinleck’s morning conferences with his army chief, navy and air force staff officers which, as the day of battle came nearer, went into more and more detail of the deployments of the Eighth Army. And every evening, Colonel Fellers sent the details to Washington, and busy interceptors in Bari recorded them, busier interpreters translated them, and their superiors forwarded to Rommel whatever they considered relevant.
Hitler remarked:
It is to be hoped that the American Minister in Cairo continues to inform us so well over the English military planning through his badly enciphered cables.
For several months the Führer’s hope was fulfilled, and the damage was considerable. The enemy was given vital information about the reinforcement of the besieged island of Malta. They also discovered the exact details of commando raids to be carried out against airbases in Italy, with the result that the men involved were wiped out as soon as they reached their targets. David Kahn, the author of a book on German Intelligence, wrote that:
Fellers’ messages provided Rommel with one of the broadest and clearest pictures of enemy forces available to any Axis commander throughout the war.
Fortunately for the Allies, the Black code was replaced by the Americans just as Rommel was about to attack Alexandria, and the new code was not broken. At the moment that Montgomery was preparing for his stand at El Alamein, the Axis suddenly lost its source of information and consequently the battle that ensued. The Allies, too, had detailed knowledge of their opponents’ intentions and continued to receive reports up to and throughout the battle. Winterbotham commented:
Before Alamein, Rommel might have caught Montgomery by surprise. At best it would have totally disrupted the preparations for Alamein. With our exact knowledge from ULTRA of just what Rommel was going to do, his attack was met and beaten off. Alamein became the turning point from bare survival to aggressive victories.
There had been significant changes in British command. First Wavell and then Auchinleck had been replaced as Commander-in-Chief Middle East. The job was given to General Harold Alexander, and command of the Eighth Army was vested in Bernard Montgomery, a charismatic and determined leader who had a personal fixation with defeating Rommel. He did this by waiting for months, during which he organized the operation in intense detail, made contingency plans for every possible situation and ignored demands by Churchill for a swift victory, while building up men and resources until he had absolute superiority in both. When finally he was ready, in October, Montgomery launched a massive offensive from El Alamein that sent the Afrika Korps reeling westward again. This was to be their final retreat.
A self-evidently crucial factor for both sides was supplies. The movement of both these mechanized armies depended on a steady supply of fuel, and they required immense amounts of ammunition. More mundane items, such as uniforms, wore out rapidly in desert conditions and had to be frequently replaced.
Ultra informed Montgomery of an acute supply shortage for the Afrika Korps which, despite having captured vast quantities of Allied equipment at Tobruk, was desperately short of fuel and ammunition. Supplies were brought to the Afrika Korps largely by sea and, unable to reach the Mediterranean via Gibraltar, the convoys sailed from southern Italian ports. Because Enigma told the Allies precisely when those convoys would be sailing, it was possible to arrange their sinking by the Royal Navy. Since the precise nature of these attacks might have suggested to the enemy that their ciphers had been broken, a ruse was customarily played out: a spotter aircraft, or a squadron of planes on patrol, or a stray Allied vessel, would be sent to the convoy’s route. Once the ships knew that they had been seen, there would seem to be nothing unusual about the fact that an attack swiftly followed.
The role of Ultra in preventing supplies from reaching Rommel’s armies was thus highly effective and absolutely vital. Not only materiel but also men were prevented from reaching the enemy through the work of the codebreakers. A member of a North African SLU, Squadron Leader AL Thompson, remembered a successful interception:
There was one incident in North Africa at this time that got rather near the bone. We had an Ultra signal in the middle of the night that fifty JU52 aircraft laden with German paratroopers were flying into Tunis. I had to rush down a rough hillside covered with stones and rocks, and the haunt of puff-adders, with only a small torch to guide me. Half-way down a bird shot up from under my feet and gave me a bad fright. Eventually it was arranged that two squads of Spitfires on patrol accidentally ran into the German formation and shot down 39 of them. For some time after this I was a bit worried that the Germans might consider this a bit too much of a coincidence, but fortunately nothing happened at all, so obviously they didn’t suspect anything unusual.
Group Captain Winterbotham knew where the credit belonged for winning the supply war:
It was ULTRA which denied all seaborne supplies to Rommel’s retreating army and forced him to withdraw right into Tunisia.
At this time Ultra was giving us a very full picture of not only the enemy’s intentions but of his build-up of troops and even the ports and times of departure of his supply ships. As the war progressed and more and more sophisticated weapons were employed the value of Ultra became more and more a question of denying the enemy his supplies of arms and fuel, and for this purpose our information was proved to be completely accurate and of course invaluable. There were one or two occasions when we sank their transports where the German Abwehr were asked to investigate. We saw the signals both for the requests and for the replies, and it was a great relief when the replies were always completely negative. Another factor which always assisted us was the strange German way of thinking which seemed to make them run on rails so that when they did anything, one could be pretty certain that they would do it again.
From the other perspective Rommel himself, looking back on the campaign, acknowledged the fact that lack of equipment had cost his soldiers victory at a time when, before the arrival of major Allied forces, it might well have been within their grasp. He had:
… discussed the possibility of surprising the British at Agedabia and knocking out the limited force they had there. This was something that could naturally only remain a theoretical discussion, since not only had we no petrol, we didn’t even have the anti-tank units necessary for such a plan. The central point for supply was no longer Tripoli as at the end of 1941, but had to be Tunisia, making it yet more impossible to assemble the stores and equipment needed for such an operation.
Once driven into Tunisia, Rommel’s troops faced a large and fresh Anglo-American force supported, as always, by a seemingly uncanny knowledge of his own plans. Winterbotham wrote that:
In North-west Africa we and our new allies, the Americans, were ensured by ULTRA of both surprise and almost total lack of resistance for the seaborne operation, and the final battles in Tunisia were fought with full knowledge from ULTRA of Rommel’s and von Arnim’s counter-attacks and the details of the positions held by the enemy.
An important element had been added to the Allied effort with the arrival in the eastern Mediterranean of SLUs that served both British and American commanders. Oliver Reece remembered that, before they deployed on the African mainland with the invaders, these codebreakers were obliged to operate from cramped quarters in a nearby British territory:
Gibraltar was bursting with personnel and SLU was packed into a small office in the army barracks. To ensure radio silence, and to prevent the enemy detecting the presence of our crack operators, whose Morse touch would be recognizable to their German counterparts, all communication from UK was by commercial cable on one-time pad, messages reaching the SLU office in batches by ‘hand of officer on a motor-cycle’.
Operation Torch, the Allied occupation of Morocco, took place on 8 November 1942. SLUs were attached to General Patton, General Spaatz (US Army Air Force), Air Marshal Sir William Webb (Royal Air Force) and General Anderson (British Army). At least one of the groups went ashore as soon as the landings had taken place. Squadron Leader SF Burley was with one of these and explained how the unit operated:
We arrived at Algiers in the early days of November 1942. Our first set-up was in a small hotel off the square close to the Place du Gouvernment. It wasn’t funny working in a bathroom and a bedroom but now we were receiving ‘real’ signals and we were to put into action our one-time-pad training. Signal reception was under the control of the Special Communications Unit (SCU) and it would seem at times wasn’t very good and there were many garbled groups to be sorted out, but overall we were able to deliver the material. Our radio operator was then working a suitcase receiver.
As the campaign in North Africa gathered momentum, an increasing number of senior generals arrived in the theatre. All had access to Ultra, and therefore required the service of an SLU. Units were set up in Gibraltar, Oran and Casablanca, and there were ultimately to be another six in the Mediterranean. The commander of the invasion force, General Eisenhower, established his headquarters in Algiers, at the Hotel St George. With him were a galaxy of talented subordinates: General Alexander, Admiral Cunningham, Air Chief Marshal Tedder and General Bedell Smith.
Squadron Leader ‘Tommy’ Thompson’s SLU worked with Eisenhower, and explained that the low profile adopted by SLU was a matter of policy:
I often met General Eisenhower in the St George Hotel and if it was first thing in the morning he invariably said ‘How are you?’ which I soon learned was the American way of saying good morning. He was of course extremely glad to get anything in the way of information from the material we could give him. The material itself went under the code name of Ultra and the number of people at the headquarters who were allowed either to see it or even to know of its existence was very limited. Its security was considered above that of Top Secret.
It had been explained to me that one of the reasons why the SLUs were kept on a form of low rank was to make them inconspicuous wherever they went. For instance, the cipher personnel with the SLUs were sergeants – true, they had been hand-picked and were a wonderful lot of men. I myself started off as a Flight Lieutenant but became a Squadron Leader later on. The Group Captain explained to me that he himself retained the rank of Group Captain so that he could slip in and out of any headquarters without any undue fuss or anybody asking what he was doing, so that it was really a matter of personality with our low ranks that enabled us to get on with the commanding generals.
When not quartered in hotels or villas, the units travelled with fighting units, eating and sleeping in their own tents. AL Thompson remembered that they shared every form of discomfort with the troops:
Life up in the mountains was fairly hard. At about 10,000 feet, the nights were cold with rather leaky bell tents and hurricane lamps by which we had to work all night to keep the flow of Ultra going and there were morning mists up to your knees. One of our customers whom I had to go and see each day was Air Marshal Cunningham commanding the Tactical Air Force. It was a rough path through the scrub and I found myself being followed by a dozen wild dogs. I knew they all had rabies so I had to shoot one before they left me alone.
Their true function had to be concealed not only from their own comrades but from occasional visiting neutral observers, no matter how seemingly benevolent they were:
We had a visit from a Turkish military mission. Quite naturally I didn’t want these people wandering about my tent and complained, but the British escort said don’t worry, they always sleep very sweetly after lunch, so I presumed they put something in their drinks.
They discouraged the curiosity of those around them by giving the impression that they were merely a signals unit. Unlike an ordinary unit, however, they could invoke some highly impressive influence if necessary. As SF Burley remembered:
It wasn’t funny being asked what your function was and having to find a suitably evasive answer. The question of obtaining transport sometimes raised difficulties and it was necessary to resort to telling the [Motor Transport] people that if they wanted confirmation that they were to let us have what we required then they should ask the Commander-in-Chief. That always did the trick. Most times we received every support. They were so appreciative of getting Ultra from the SLU that it was important we were able to function properly. We also had the added help of knowing that should it become necessary, owing to the lack of co-operation, we had only to send a signal back to Group Captain Winterbotham and he would put the pressure on. His ‘special’ pressure was of the highest order!
The SLUs also differed from virtually every other military formation in that they had no clearly defined hierarchy or obvious commanding officer. Thompson explained:
I was not under the command of anyone at all in the theatre of war, but only under the command of Group Captain Winterbotham in London, so that although I was attached to various commands I didn’t come under their jurisdiction and was completely independent except for being fed. I always made it a rule to avoid making my unit look anything out of the ordinary, particularly in tented areas so that one became part of the landscape and no-one ever bothered us. We carried no papers as proof of what we were and there were times when one had to push one’s way through interference.
SF Burley outlined the significance of the material with which even a humble mobile SLU was dealing:
It was now clear to us that we were receiving from the UK the decoded original signals of the German High Command, even from Hitler himself. This was the information we passed on to General Anderson and his intelligence staff who were in fact in the position then of knowing exactly what the German High Command were proposing to do in the future, or an appreciation of the battle state, movements of troops, aircraft, naval ships etc. etc. Such was the vital importance of this information that the material received from BP had been given the code name Ultra, the most secret of any intelligence information used during the Second World War. The army commanders and those of his intelligence staff who were to handle it were very limited and it was made very clear to them that any question of its misuse would [mean that] the whole operation would be compromised and the Germans would immediately realise that their codes had been broken, and [therefore] the security of Ultra was only passed on to those restricted few who were briefed a) on its contents and b) as to the use thereof under no circumstances whatsoever was it to be repeated, certainly not to be relayed by signal. Ultra was only transmitted on special high frequencies by the SCU to the SLU unit attached to the Commander. It came no other way and was only handled by them.
He described the tight security surrounding every scrap of paper that contained Ultra information:
Once again our unit was in a somewhat ‘no-man’s land,’ isolated in our bedrooms etc. Security as ever was No 1 priority. As our signals were not received through the usual links we were something apart. A very secret unit doing a job that was distinct from any other in the HQ. It should be pointed out however that it was always necessary for the SLU to make itself as unobtrusive as possible. Its function was to deliver to the commanding generals and their intelligence staff the material we were receiving direct from England on our own wireless link. This was the primary object of its operational performance. The signals were delivered by the hand of officers and it was their duty to see that they were then handed back. No recipient was allowed to ‘slip them into their pockets,’ so to speak.
The temptation to do precisely that was sometimes too much for senior officers to resist, and the job done by SLU members required considerable diplomacy. John Lamont found that problems could also arise with the adjutants and assistants of commanders, who had to be tactfully prevented from seeing the messages:
We were on attachment to the army HQ and had responsibility for security of the unit and particularly for the security of the Ultra intelligence material fed to General Anderson. In this respect we were under the clear orders of Chiefs of Staff in London. This sometimes put us in some difficulties with a variety of majors and colonels who, of course, were not in our picture. Often they tried to pull rank on me, at that time a Flight Lieutenant.
The most notable event was a brush with General Anderson himself. Our modus operandi was that we handed a message to Colonel Dawnay (Anderson’s Number Two) and collected them for burning shortly afterwards. On one occasion I found that a very high priority message had not been returned, and saw Dawnay about this. He said that although he had asked Anderson for the message, he had decided to keep it. He also said the General was going forward in the next few hours. This was obviously up to me as Dawnay refused to try again. Perspiring slightly I went to see Anderson and asked for the message to be returned to me for destruction. He categorically refused to hand it back. I was obliged to remind him of the vital need for security of the source, both in necessity to avoid compromising the information by precipitate action, and the physical existence of the message itself. He claimed it was perfectly safe with him. I was obliged to tell him that I was under strictest orders to burn the message and report direct to Chief of Staff if prevented from doing so. Anderson was a dour, taciturn Scot and with a very bad grace indeed pulled it out of his pocket and handed it to me.
Fortunately not everyone regarded Ultra signals as their personal property and most recognized that, if security were breached, the source of this war-winning intelligence might dry up:
As a contrast a similar matter occurred with General Alexander, who was just taking over the new 18 Group and was due in North Africa. We had high priority information addressed to him and handed it over to him. He wanted to take the message forward with him to Anderson’s command post. I reminded him of the security vital to protect the source and that I had responsibility for destroying the physical message. His reaction was immediate and he was delighted that I had reminded him.
Like Alexander, the senior American General, Dwight Eisenhower, was polite and appreciative of the rules governing the use of Ultra. Squadron Leader SF Burley commented:
The requests to receive Ultra were so vital that we were providing all Commanders-in-Chief of both the army and the air force with an SLU attached to their headquarters. During the night, after a very busy day, we received a signal ‘Ultra Eyes Only’ for General Eisenhower from the Prime Minister. It was only to be delivered to the addressee himself. I took it along to his sleeping quarters, and having been stopped by the guard, was passed over to his G2 Intelligence Officer and was duly ushered into General Eisenhower’s bedroom. A somewhat sleepy 5 Star Commanding General woke up to see one RAF officer with a slip of paper for him. He put on his glasses and read it, re-read it and thanked me and handed it back to me. This only goes to prove how much the material was appreciated. There was no question of a senior officer saying something to the effect – ‘I’ll take that and pass it on’. For one thing, we wouldn’t let it out of our hand, and in this instance ‘eyes only’ meant what it said. We endeavoured as far as possible to be unobtrusive, but such was the importance of our work that entry to see Commanding Generals was never queried.
It seemed to be an almost universal experience that a commander would be delighted to receive a visit from an SLU officer, while his assistant – a man of high rank himself – was irritated at being bypassed and kept from knowing the contents of the messages that were delivered. Squadron Leader OB Reece recalled that:
All of the recipients were very appreciative of our service, indeed quite avid to receive Ultra. Our service to the Navy was limited and I suspect complementary to their own channel. However, such personal messages as came in for Admiral Cunningham were received by him with great courtesy. Also Air Marshal Tedder always received any ‘personal only’ messages with appreciation. However, Tedder’s outer office assistant, you might say his ‘doorkeeper’, a certain Wing Commander, was anything but courteous. On one occasion, having unsuccessfully tried to get a ‘personal only’ message off me, when I came out of Tedder’s office he said ‘What shall I do with that tripe when it comes out of his waste-paper basket?’ to which I replied, ‘I do not think you will find the message in the Air Marshal’s waste-paper basket, sir, but I do assure you that if I ever have a personal only message for you, I will make certain that nobody but you receive it.’ In general I found a better welcome from the ‘top brass’ than from their underlings. It seemed as if bypassing them with personal messages resulted in disturbing the cathedral calm to which they liked to accustom themselves.
No doubt in the many cases that occurred similar to the above, higher ranks for SLU personnel would have much facilitated the presentation of Ultra. However, we did not sign on for an easy job and speaking personally I was never much impressed by rank, my own or anyone else’s.
Reece found that the perspective – the historical overview – he gained on the war was more than adequate compensation for the monotony that often characterized his job:
Despite the long hours of prosaic drudgery entailed in providing a day and night Ultra service, I found the job fascinating. Unlike the average wartime job which confined the view to a minute fraction of the whole, Ultra provided a spectator like myself with a panoramic view of the entire war operation. Also, unlike the ‘need to know’ limits imposed by conventional intelligence, in Ultra one was able to see the start and finish of an operation, thus appreciating the value of one’s contribution. For example, in the evening a signal about a tanker leaving Bari with fuel for Rommel is rushed to the customers and the following morning comes the news that the tanker is sunk, an immediate confirmation that one’s vigilance and despatch have helped to put a nail in the coffin of the enemy’s plans for Egypt.
Pursued after Alamein by Montgomery’s much larger armoured force, the Afrika Korps had once again retreated westward. With America in the war, Allied troops (four divisions of the US First Army) had been landed at Tunis and blocked his way. He was not yet defeated – indeed he was able to beat the Americans in battle at the Kasserine Pass – but with hostile armies on two sides and Montgomery pressing hard from the east, with supplies disrupted and uncertain, and with control of the air in Allied hands, the Afrika Korps was doomed. By the summer of 1943 it had surrendered. The Eighth Army had pursued it 1,500 miles in just three months. The Allies took more than 150,000 prisoners.
As with much else in the war, the codebreakers were the first to know of important developments. A young woman at Bletchley Park remembered when confirmation arrived of the Axis withdrawal from North Africa:
In early 1943, I was on duty on the night shift alone. We were going through a sticky period; the Italian codes were making no sense. I decided to have one more go … suddenly a message began to appear. I shouted for Leonard Hooper in the next room and he rushed in and I told him the message was making sense. He literally seized my paper, shouted ‘You’ve done it! You’ve broken it!’ and tore out of the room and down the passage to Josh Cooper. There was great excitement that night, for the message was that the Italian air force was preparing to leave North Africa. The news was radioed to the RAF in Egypt and subsequently night fighters shot down almost all the Italian transport planes. For this breakthrough, I was summoned to Josh Cooper’s room and congratulated.
On 20 May 1943, the Allied victory parade took place in Tunis.
Once North Africa had been won by the Allies, the war was to be taken to Axis territory. The Italian satellite islands of Lampedusa and Pantelleria were seized without difficulty. The next island objective of Allied planners was Sicily. Code-named ‘Operation Husky’, this task would involve American, British and Commonwealth troops in a combination of airborne and seaborne forces. The invasion would be launched from Alexandria in the first days of July 1943. Once Sicily was cleared, the Allies would cross the Straits of Messina and invade the Italian mainland. For the first time, one of the enemy powers would be fighting on the soil of its own homeland.
Winterbotham, who was visiting the Mediterranean theatre at the time, stressed the role of Ultra in the execution of this plan:
I found that at all the main SLU stations a great deal of high-level traffic was being sent over the SLU channels by the chiefs of staff in London to Eisenhower and Alexander, and also between the various commanders-in-chief in the Mediterranean area. This was primarily because so much of the planning for Sicily and Italy was based on Ultra information and any discussion or change of plan based on intelligence had rightly to be sent over our own channel; added to which the top brass as well as Winston Churchill found our channel quicker than the normal signals organisation, and its maximum secrecy was useful when personalities had to be discussed. The SLUs were, in consequence, working flat out.
He also observed that the SLUs were now an accepted, essential and greatly appreciated part of the entourage of the senior commanders, who had become not only accustomed to a regular supply of information but also almost entirely dependent on it:
All the SLUs were now old hands at the game. They had worked out methods of keeping on the air even in times of rapid movement, since they told me that the commanders didn’t like being without their Ultra even for ten minutes.
The staff had to work round the clock to process a workload that could reach as much as 200 enemy signals a day. Some of these signals had given away the location of the headquarters of General Kesselring (Commander-in-Chief Mediterranean) in Sicily, which was in a hotel at Taormina. As a result, the RAF shortly afterwards destroyed the building in an air raid. Though their intended victim was elsewhere at the time, a number of his subordinates were killed.
Ultra made an immense, immeasurable contribution to Operation Husky because it described in exact detail the enemy positions and revealed that neither the Germans nor the Italians knew when, where or even if the attack would come. It showed that Hitler shared this uncertainty, and therefore that it was unlikely that reinforcements would be sent to Sicily in time to have any effect. As a result of this intelligence, Allied paratroops were able to capture strategic points that prevented German panzer units, held in reserve in the centre of the island to be rushed to any invasion beach, from doing so.
When it arrived off the coast on 10 July, the invasion fleet (which had been spotted only the previous day by German observers) had achieved surprise, and thus tactical advantage. Though Kesselring was an able commander and signalled for reinforcements as soon as he knew that the Allies were about to land, it was too late. John Lamont was with an SLU that went ashore after the initial assault:
We had very strict orders not to be taken prisoner! This was possibly the first time an SLU had to go in on a landing from the sea in a landing craft. It was almost certainly the first time an SLU unit had been attached to General Patton, who was well known as a very adventurous type. He was considered to have a certain contempt for the word security in terms understood in SLU. However, it was very good to have a session with our chiefs, and we acquired the necessary equipment to destroy our documents and w/t equipment at short notice.
On the morning of the 15th July, we located it and reported to General Patton at Gela. Despite prior warnings that the General was a real rough type, I was surprised at the very cordial reception we had. He said: ‘Mighty pleased to have you British boys come along with me.’ He introduced me to Colonel Koch [his Assistant Chief of Staff] and to [General] Bradley and several of his Corps Commanders. Koch arranged a camp site for us alongside his tent and we discussed the security arrangements to be made in the present and anticipated moves of the command post for future operations. We moved our unit up and located tents and vehicles on the area.
Several units of panzer troops and parachutists were ordered to Sicily, but it took valuable days, and even weeks, for them to arrive. General Patton knew, through the efforts of Lamont and his colleagues, that the enemy did not yet have the necessary strength to oppose him and he drove his armoured units across the island to Palermo, reaching the Straits on 8 August. Less than ten days later the conquest of Sicily was complete. Winterbotham wrote that:
In Sicily Patton, who was made aware by ULTRA of the precise position of the German panzer units and the direction in which they were moving after the Allied landings, slipped round their flank and got to Messina almost before the Germans could get across to Italy.
The capture of Italian territory precipitated a collapse of extraordinary speed. Italian soldiers had been expelled from the African colonies and defeated in the desert. They were fighting and dying in terrible conditions on the Eastern Front. At home, civilians were enduring rationing and air raids. War-weariness and disillusionment with Fascism were widespread. Many Italians saw the arrival of Allied troops as a signal that the war was lost. To avoid the devastation of their country and its priceless artistic heritage, an immediate end to the conflict was necessary.
On 25 July, while the Allies were still fighting in Sicily, Mussolini was dismissed by Italy’s king, Victor Emmanuel, from his position as prime minister. He was also removed from office by the Fascist Grand Council, placed under arrest and sent to the far north of the country. His successor was a senior military man, Marshal Pietro Badoglio. Trusted by both Allies and Italians because of a long history of aversion to Fascism, Badoglio sought to sign an armistice as soon as possible. The necessary approaches were quickly made – through the medium of a captured Special Operations Executive radio operator. Italy was not only to leave the Axis camp but to join the war against its former comrades. It took some weeks to negotiate conditions, but peace was finally signed on 8 September, the day on which the Allies crossed to mainland Italy. John McCaffery, a member of SOE, recalled the circumstances. A colleague of his, a fluent Italian speaker, was parachuted into Lake Como by British aircraft on their way to bomb Milan. No one had appreciated, however, the interest taken by local people in these operations, and thus the agent’s chances of making an inconspicuous arrival were extremely slim. As McCaffery wrote:
It looked a fine plan on paper. But first of all there was bright moonlight, and seemingly, many people living on the shores of the lake had the habit of turning out to see the Milan bombings as if it was a fireworks display. Dick and his parachute therefore floated down to the water before a large fascinated audience.
Quickly arrested, he spent three weeks in captivity before being summoned to an unusal task:
When the King and Badoglio decided to sue for peace, they thought that initial radio contact would be faster and more secure than attempting to approach through emissaries. Incredibly, using state radio technical experts, they failed to make the contact they desired; and then someone remembered the British parachutist and his W/T set dropped into Lake Como. Dick was fetched poste haste and asked whether he would oblige them. He replied that most certainly he could, and to the astonishment of the experts, who had viewed his small set with incredulity, within half an hour he had done so.
It was thus over Dick’s little W/T set that the first Italian peace overtures were made, and his ducking [in the lake] had been justified on a bigger and more historic scale than we had ever imagined.
Hitler at once sent more German divisions to the north of Italy, to hold any Allied advance up the peninsula, but also to be prepared for an attack on the Balkans, which the Führer considered likely. He created a new army, comprising both reinforcements and formations already in the region, commanded by Rommel. During this period of frantic reorganization, the signals sent by Enigma told Allied commanders everything they needed to know about the strength and dispositions of the German units.
The Germans were expected to evacuate the south of the country and withdraw toward Rome. Movement was slow and German divisions were still in the south when the Allied landings took place, which meant that resistance was fiercer than had been hoped. The landings were carried out first in Calabria, then farther north at Salerno, south of Naples. Opposition there was insufficient to stop the invaders getting inland. The geography of the country had made it comparatively easy for the defenders to create the ‘Gustav Line’, a protective wall across the narrow peninsula from the Tyrrhenian Sea to the Adriatic. Italy’s long coast, of course, made it possible for the invaders to bypass this. While troops already ashore drove north toward the Gustav Line and the capital, another force came ashore in January 1944 at Anzio – halfway up the boot of Italy and a short distance from Rome. Within this region would be fought the two most significant battles of the campaign, at Anzio and Monte Cassino.
Alexander may initially have been pleased at progress, but he was to have little cause for long-term satisfaction. Ultra had suggested to the Allies that they need not expect fierce opposition, and they had got ashore without difficulty. The failure of General Mark Clark, the American commander, to follow through by moving swiftly inland was to squander this advantage. The Germans counterattacked with vigour and almost succeeded in wiping out the beachhead. The Allies were to spend four months clinging to their toehold on the beaches, protected largely by the firepower of the ships offshore. The Italian campaign was to be slow going.
The troops farther south had troubles of their own. Monte Cassino was an ancient monastery set on a mountaintop that commanded the road to Rome. Such a setting for defence could not be ignored and the Germans had fortified it. On 12 May, in the middle of the night, the assault on it began. It was suicidal. Though Allied airpower quickly reduced the venerable buildings to rubble, the defenders had dug into the surrounding rock and were making the most of the mountain’s protection. Any waves of attackers fighting their way up the steep slopes had little hope of avoiding the raking artillery and machine-gun fire that poured down from above. Days and nights passed, and still the ruins held out.
In London, Churchill was becoming anxious. The Germans’ successful containment of the Anzio beachhead had been of immense value to their morale. Now Cassino was proving another debacle. Churchill needed the campaign speeded up – and Rome taken at once – because Operation Overlord, the long-awaited stab at northern Europe that would open the final chapter in Germany’s defeat, was scheduled to begin in early June. To capture Rome would, in a symbolic sense at least, suggest that the Italian campaign was won.
Winterbotham remembered the anxious days during which he, and Churchill, followed the progress of the armies:
On May the 13th I had a telephone call from the Prime Minister. He asked that I meet him at his flat that evening at 9 p.m. and would I bring round all signals dealing with the Cassino front. It was a cold evening for May and the Prime Minister was sitting in his boiler suit deep in his green leather chair in front of a good fire. He looked tired. I had given him the various small details of the fighting which had come in during the afternoon. When he said ‘Is that all?’ I had to say that I was afraid it was so. We went across to the map room where the few alterations I had brought over were flagged up, but Churchill was obviously puzzled and disappointed. In his usual courteous manner he thanked me for coming over and then, with a broad smile, he said, ‘See that I get anything more first thing in the morning. I think you will find there will be something of interest.’ It was now late but I phoned the watch at Bletchley and warned them to keep their eyes skinned. It came through about 3 a.m. and Mrs Owen’s knock on my office door with a welcome cup of coffee. The French Moroccan troops had scaled the mountains south of Cassino. Kesselring had reported to Hitler that ‘the whole Cassino line was now in danger’. That day signals reported to Berlin that now both the British and the Americans were gaining some ground. On the fifteenth Kesselring sent a signal to Hitler reporting a breakthrough by another strong French force over the massive Monti Aurunci which dominated the Liri valley and the supply routes to the Cassino line. On the sixteenth came reports from Kesselring of the successes of the British and Polish forces around Cassino, and then on the seventeenth came the one we had been waiting for: Kesselring ordered the evacuation of the entire Cassino front, since, as he said, the French had penetrated twenty-five miles behind the German lines. Bletchley was in good form and Churchill, Alexander and the US chiefs of staff in Washington had it within a few minutes of its despatch by Kesselring.
Cassino was captured, though at a terrible cost in lives and destruction.
Having broken out from Anzio, General Clark disregarded instructions to cut off the retreat of Kesselring’s troops by moving east. Instead he headed north for Rome, 30 miles away, in a vainglorious desire to be first to enter the city. Kesselring had decided not to defend it, thus saving considerable bloodshed as well as the ruination of what is perhaps the world’s most culturally important city, and the Allies knew this through reading the signals that passed between him and his chief. They marched into the Eternal City on 4 June 1944, 48 hours before D-Day. Winterbotham was scathing about the chances that had been squandered:
It was Mark Clark who, in that dreary slogging match up through Italy, three times did not use the opportunities ULTRA had provided, and which Alexander had planned for him: first at Anzio, then after the fall of Cassino and later north of Rome, to cut off and surround Kesselring’s armies. It was Alexander who, knowing the precise distribution of German troops at Cassino, planned the surprise attack over the mountains and it was France’s General Juin who so brilliantly carried it out.
To reach Rome the Allies had passed through two further German defensive barriers – the Adolf Hitler Line and the Caesar Line – which Kesselring had chosen not to contest. The Germans withdrew northward to a further position, the Gothic Line, which ran from Pisa across to Rimini over the Apennines. Here they intended to make a stand, and defences were rapidly constructed. Though many British military clerks and other administrative staff were to remain in the capital serving the Allied Control Commission, the fighting troops continued their trek northward, and with them went the SLU. Miss L Addey explained that travel in the slow-moving convoys was a dispiriting experience, and efficient organization was vital:
A rapid advance by road was very complicated because of the vast amount of traffic that a mechanised army needed to maintain itself, and this put a great deal of strain on the existing roads. When a unit like ours moved with all its vehicles, between 90 and 150, very careful timing of convoys was required to avoid a snarl-up of traffic. In fact, the problem was almost like railway signalling in the rush hour.
There had to be traffic control points every 10 miles or so to ensure that convoys were on time, and to make alterations if they were not. There had to be signposting of roads, police, guides and so forth. Provision also had to be made for recovery posts and vehicles so that damaged trucks and tanks could be got off the road. In addition, there was usually a mobile recovery patrol and this was as busy as the AA on a Bank Holiday Sunday. Recovery was a REME [Royal Electrical & Mechanical Engineers] responsibility and the Brigade REME vehicles travelled with our convoy to deal with breakdowns.
Kesselring’s retreat was ragged, and had the Allies chased their enemy more decisively they could have got between the German armies. Clark, once again, was too hesitant to seize the opportunity. The Germans fell back on the Gothic Line and waited.
Ultra remained as important, and as forthcoming, as ever. The traffic between Kesselring in the Apeninnes and Hitler in Berlin had included an order from the Führer that the Futa Pass, one of the few paths through the mountain range, was to be defended (in the phrase that Hitler had used since Stalingrad) to ‘the last man and the last bullet’. Armed with the information that defences would be concentrated there, Clark’s Fifth Army was able to launch its attack through a nearby pass instead. Though fighting was heavy, the American armies had enough momentum to push their way through into Lombardy. The last and most formidable barrier had been crossed. Though Kesselring appealed for reinforcements, he received in return the demand to release men from his own armies for service in France, where the advance of Anglo-American forces made the need for men far more urgent. Continuing his retreat north Kesselring, as he had done in Rome, spared Florence the agony of defence and therefore destruction.
The Italians had switched, in a moment as it seemed, from enemy to ally and for members of the Anglo-American forces this could create difficult situations. AL Thompson, attached to General Alexander’s headquarters, was concerned at the presence there of a distinguished guest who roamed at will among the secrets. This was Victor Emmanuel, still for the moment King of Italy (he would abdicate shortly afterwards). Howard recalled:
It was [at General Alexander’s villa on Lake Bolsena] that the late King spent some time staying with Alexander under a nom de guerre as General X. They had erected a nissen hut war room in which maps based on our material were displayed. It was guarded day and night by a duty Intelligence Officer who was in the Ultra picture. I may have been too security-minded, but seeing the King wandering about everywhere and bearing in mind that no-one not directly involved could see our material I wondered whether he was allowed to do so. I sent a personal signal to London asking whether General X was allowed to see our material. It took quite a long time before I got a reply and the answer was no. It was only at the end of the war that they told me I had got all the security services running around in circles as no-one had told them who this general really was.
Winston Churchill paid a visit to the Italian front to see the conditions there for himself, and for a few weeks Thompson found himself acting as SLU officer to the prime minister. Churchill, like most of the military commanders, treated Ultra staff with particular kindness, perhaps because he knew that they would receive no adequate recognition for the contribution they had made:
After a somewhat idyllic stay at Bolsena we went forward again and made camp in a great feudal estate a few miles south of Siena. It was here that Winston Churchill stayed with us for about three weeks. He was actually living in a villa close to the camp and I began to give him the full service. He was very pernickety about the way our signals were presented to him and they had to be typed in capital letters in three-lined spacing. I think my face must have fitted as he was very friendly to me from the start and grew increasingly so as the days went by. It may have been of course that I gave him everything he wanted and there was never a slip-up. I remember one occasion when he put his arm around my shoulders and dragged me to a large wall-map saying: ‘Come along my friend and tell me how the war’s going.’ Another night I had to find him to deliver a message and discovered him in a small marquee having dinner with Alex and a very distinguished company indeed. I gave my name to the Warrant Officer at the entrance and Winston turned round in his chair and said: ‘Come in and sit by me my friend, get a chair for the Squadron Leader, and what are you going to have to drink?’ So there I was plonked down beside him on his left hand side at the top of the table as one of the party. I already knew quite a few of these people through previous contacts and Winston turned to me and said: ‘I don’t think you know the Chief of the Imperial General Staff, Alan Brook,’ and I replied, ‘No, sir, I haven’t had that honour,’ whereupon Sir Alan rose to his feet and solemnly shook my hand across the table. It was a marvellous gesture by Winston. I think I stayed for some considerable time before I made my excuses because I was listening to a most fascinating high-powered policy debate.
Though clearly Kesselring’s absolute defeat was now only a matter of time, his armies remained dangerous until the end of hostilities. He negotiated their surrender on 2 May 1945, only a week before the war in Europe ended, and his forces at that time numbered almost a million men. This was the largest army in history to capitulate.
The Italian Campaign could not have been won without the information provided by the SLUs. It had proved so fundamentally vital to Allied chiefs that Winterbotham was later to write:
Not only the commanders in the field, but also Churchill, Roosevelt, and the Allied chiefs of staff had all the cards in the pack spread out on the table face upwards.
By that time, however, most of the codebreakers had long since departed. The war in Italy had clearly been winding down for some months and attention had shifted to other theatres. Principally this meant the Far East, where resources were being assembled for the final showdown with Japan. SLU members were posted back to Britain for retraining, or were sent direct to join units in India and Australia. Flight Lieutenant (Josh) Reynolds wrote:
November 1944 and the situation in Italy was gradually closing on the enemy and on the other side of the world attention was concentrating on Japan. Work for the large SLUs in Italy had decreased considerably so we were not surprised when a call came asking for volunteers to strengthen the SLUs in India and South East Asia Command and also Australia and the South Pacific area now that the Americans and Australians had gone over to the offensive.
Captain JN Howard’s last memory of Italy was of a trophy he carried with him on the journey home – a highly appropriate souvenir:
I have a hazy recollection of flying back to London with the innards of an Enigma machine which was found at German army headquarters when they bunked out of Italy. I remember something about fears that had been expressed that the day settings had been mucked up by a crowd of sergeants who had found it. It seems they had been using it to gamble on like a fruit machine but happily no damage had been done and the back-room boys at home must have found it very useful.