The decision to invade France in 1944 was taken at the Casablanca Conference in January 1943. General Morgan was appointed Chief of Staff to the future Supreme Commander and established his headquarters at Norfolk House, St James’s Square, in April of that year.1 On 26th April he received a directive from the Combined Chiefs of Staff which, besides instructing him to prepare plans for a full-scale assault against the Continent as early as possible in 1944 and for a return to the Continent in the event of German disintegration at any time, also demanded ‘an elaborate camouflage and deception scheme extending over the whole summer with a view to pinning the enemy in the West and keeping alive the expectation of large-scale cross-Channel operations in 1943. This would include at least one amphibious feint with the object of bringing on an air battle employing the Metropolitan Air Force and the Eighth US Air Force.’2 The deception plans which were prepared in compliance with that instruction and which received the name of COCKADE do not strictly lie within the scope of this report. Nevertheless, as they had a bearing upon subsequent events, a short account is included.
COCKADE had two distinct objects: to contain German forces in North-Western Europe, thus preventing them from being used on the active fronts, and to destroy German aircraft. The plan comprised three connected operations: TINDALL, the threat of a landing in Norway; STARKEY, of a landing in the Pas de Calais; and WADHAM, of one in the Bay of Biscay. STARKEY and WADHAM, so the story ran, were to be complementary operations. After the bridgehead in the Pas de Calais had been established by British forces, an American landing was to take place in Western France with the object of opening Brest, which could then be used to land troops sailing direct from the United States. The forces in the United Kingdom being held inadequate to support all three plans, the French and Norwegian assaults were presented as alternative undertakings. STARKEY was the most important part of COCKADE inasmuch as it included an elaborate embarkation exercise3 by 21 Army Group in which the landing craft actually sailed to within a few miles of the French coast, as well as real air attacks against the Pas de Calais. TINDALL and WADHAM relied mainly on the use of wireless, dummy devices and controlled leakage.
The STARKEY assault took place on 8th September. In accordance with the prearranged story, the preparations for TINDALL, which had been progressing in Scotland throughout August, were cancelled on the 25th of that month in favour of the cross-Channel attack. It was thought that this would give emphasis to the latter. When STARKEY failed to materialise as a real operation, a public announcement explained that it had only been a large-scale exercise. Meanwhile TINDALL was revived in the North and continued until November.
In its attempt to bring the German Air Force to battle STARKEY failed. It should, however, be remembered that in the real invasion which took place a year later the Germans did not commit their Air Force until after the first landing had taken place. The measure of success which it achieved in containing German forces in Western Europe is fully considered in the ‘Historical Record of Deception in the War against Germany and Italy,4 to which the reader in search of further information is referred.
In the summer of 1943 it was argued that STARKEY would help the cover operation for the real invasion which was again to threaten the Pas de Calais in the following year. ‘It will be of the utmost importance to pin all … reserves for as long as possible. To this end, every artifice must be employed to draw his (i.e. the enemy’s) attention to his most sensitive spot – the Pas de Calais. Operation STARKEY, it is to be hoped, will have some effect this year.’5 Whether STARKEY was really an asset to deception in 1944 may be doubted. We ended by admitting that it was only an exercise. To conduct and publicise a large-scale exercise against an objective that one really intended to attack during the following year would hardly suggest a convincing grasp of the principle of surprise.
The only other bearing which COCKADE had upon the deceptive operations of the following year was to implant in the German mind a belief in one, and perhaps two, imaginary armies: the Sixth at Luton, and less certainly, the Fourth at Edinburgh.6 These were represented as having grown out of, and as being more or less synonymous with, Eastern and Scottish Commands. The Fourth Army later became a valuable part of the FORTITUDE Order of Battle. The Sixth Army we did not need again, but never succeeded in destroying. It remained a part of the German version of the Allied Order of Battle until the end of the war.
It was not until OVERLORD had been written and submitted to the British Chiefs of Staff at the middle of July 1943 that attention was turned to deception plans for 1944. At that time the view was held that preparations for the cover operation should not lag behind those which were being made for the real one. Thus the production of a cover plan for OVERLORD appeared to be a matter of immediate concern. In order to appreciate the reason for this sense of urgency and, indeed, to understand many of the opinions expressed and decisions made at that time, it will be necessary to try and recapture something of the general attitude towards deception which prevailed in the summer of 1943.
In any theatre of war, deception must operate in the main through the Intelligence channels which have already been established by the enemy. It is thus the first task of the cover planner to decide which channels are likely to work and which, if they do work, the enemy is most likely to rely upon. The whole nature of one’s deception plan will depend upon the initial assessment that one makes in this respect. The most important sources of Intelligence upon which the Germans might have been expected to rely for information about what was happening in the United Kingdom were aerial reconnaissance, wireless intercept and espionage. In all three fields we credited them with an efficiency which, as we now know, they did not deserve. Let us consider the prospect as it then appeared. Admittedly, the value of air photographic reconnaissance depends upon comparison of photographs taken at frequent intervals, and such reconnaissance over the United Kingdom had only been sporadic for a considerable time; yet the invasion was still nearly twelve months away. In the intervening period it might, and indeed was expected to, increase very greatly. Without a guarantee from the Air Ministry, which the latter was not prepared to give, COSSAC could not ignore the danger. So with spies; it was morally certain that there were no bona fide German agents at large, but it would have been practically impossible for the Security Service to guarantee that the country would not be flooded with spies during the coming months, some of whom would be bound to escape detection. With wireless intercept, the case was even stronger. Holding the entire Western European coast line, the enemy could place his stations in a continuous arc stretching from Norway to France, and thus appeared to be ideally placed for intercepting wireless traffic in the United Kingdom. Our belief in the efficiency of the German ‘Y’ Service may have been due to battle experience which had revealed its success at short range; it may also have arisen, in part, from pure lack of evidence; yet that such a belief was held is shown by the following quotation which is typical of many: ‘In the case of the British forces, except those arriving from the Mediterranean, it is known that the enemy already possesses an accurate estimate of the number of formations in the United Kingdom, the greater part of this information having been obtained, or at least confirmed, by his “Y” Service.’7 One body of evidence which seemed to support this view was provided by the German publication Das Britische Kriegsheer. A copy of this manual dated 10th April, 1942, had fallen into Allied hands some time previously. An examination of its contents had disclosed not only a very fair knowledge of those parts of our Order of Battle which had only come into being since the outbreak of war, but also, by implication, a good deal of information about the location of our forces. This could be deduced from an analysis of inaccuracies in the work. For instance, the 76th Infantry Division was located at Norwich at the beginning of 1942. Its nine battalions were correctly listed with one exception: in place of the 1st Battalion of the Leicester Regiment, the 18th Battalion of the Welch Regiment was included. In fact, the Welsh battalion had no connection with the 76th Infantry Division, but happened to be engaged in aerodrome defence at Norwich at that date. A number of similar instances were found. These clearly pointed either to the personal observations of a spy or to intercept. The matter was submitted to the Security Service at the time, who gave it as their opinion that this was undoubtedly attributable to intercept.8
These opinions on the excellency of German Intelligence methods were by no means confined to the staff at COSSAC. Thus, in a note written by the Secretary to the Chiefs of Staffs Committee on 22nd April, 1943, the following view was expressed: ‘Broadly speaking, deception has three phases. First, the preparation of the deception plan; secondly, the execution of the plan in terms of movements of men, ships, &c., and thirdly, measures to ensure that the movements become known to the enemy. The first and third phases present no difficulty. As regards the first phase, the responsibility for the preparation of the cover deception plan … has been vested … in General Morgan. As to the third phase, namely, ensuring the enemy gets to know of the deception movements and is deceived by them, this is a matter for the Controlling Officer.9 … It is the second phase, namely, the execution of the deception which is complicated. The executive orders for troops to march and for troops and aircraft or Air Force personnel to move for deception purposes, must come from the Naval, Army and Air Commanders-in-Chief concerned.’10 Had the security of the United Kingdom been accepted as absolute, the Controlling Officer could have made his channels say whatever they liked and there would have been no need for the troops to march in order to support his statements. As it was, the troop movements were to form the backbone of the whole deception plan, the Controlling Officer’s part in the business being merely ‘to ensure that the movements became known to the enemy’. In a later passage, the same letter proposed a meeting of all Commanders-in-Chief concerned, possibly under the chairmanship of the Prime Minister, and recommended that it should ‘be explained to the Commanders-in-Chief that effective deception involves the actual movements of stores, craft, troops and possibly Air Force personnel. These movements must inevitably interfere with normal training and movement.’
Having accepted this view as to the capabilities of the German Intelligence Service, the need for vast and complicated physical preparations followed inevitably. All the normal invasion preparations which would be visible from the air – landing craft, camps, hard standings for vehicles and so on – must be physically represented in those places where we wished the enemy to believe that we were concentrating and embarking our invasion forces. Furthermore the false preparations must look realistic at the ground level in order to deceive the spy. At the same time the activities of the Controlling Officer would be restricted by the extent of these physical preparations. His channels could not report a movement of troops which had not been sufficiently represented to deceive the German Air Force, ‘Y’ Service and uncontrolled spy, lest his report should be contradicted and the channel discredited. That is why the real and the cover operations had to go forward together. Unless a cover plan was produced quickly, its requirements in the shape of physical resources and demands on manpower would go by default. It was essential that the needs of both should be assessed at the same time and a fair division made.
Here, however, another difficulty arose. It was felt that it would not be easy to write a cover plan until the broader strategy of deception had been decided upon. A decision in the higher sphere was dependent upon the results of the Teheran Conference, which was not due to meet until later in the year. The problem was temporarily solved by dividing the planning into two parts, one ‘strategical’ and the other ‘tactical’. Roughly speaking, ‘strategical’ meant keeping German forces out of France, while ‘tactical’ meant keeping them away from the Normandy bridgehead. The strategical plan could wait for Teheran, while the tactical plan could be proceeded with immediately. The development of this plan will now be considered.