The collapse of Russia had not merely saved, the Central Powers from defeat in 1917, but held out to them a promise of positive success in 1918, with the realisation of their most ambitious hopes. The German Command was quick to appreciate the wholly changed situation. Masses of men and artillery had been released and the latter reinforced by vast quantities of captured armament. Once again Germany had recovered numerical superiority and that initiative which she had lost since Verdun. Cards had been dealt her such as she had not dared to hope for. She had little hesitation as to how she would play thorn. It was on the Western front, and not in the subsidiary theatres of war on the Mediterranean and in the East, that the main issue of the war would be decided. An additional reason for an early offensive in France lay in America's intervention. The submarine campaign promised no effective hindrance to the crossing of American reinforcements, and it was apparent that did Germany not attack speedily, she would once again be outnumbered in the field and thrown back on the defensive by her enemies. Within her own borders, moreover, the Allied blockade and propaganda were not sterile, and there was doubt and uncertainty, even in high quarters. For these reasons it was imperative for Germany to strike with all her might while the golden opportunity lasted. Conscious of their strength, the generals at a secret session of the Reichstag in February promised the elated deputies a complete victory in the autumn.
Their plans were boldly conceived. When General Rawlinson met his Corps Commanders in December and reviewed the possible alternatives open to the enemy, he had directed particular attention to the Cambrai front. As the point of junction between the French and British Armies, and as familiar to the enemy through former occupation, it might be expected to appear specially attractive. On the other hand, Rawlinson pointed out that no objectives of far-reaching tactical importance such as the central ridges about Arras or Ypres seemed to be within reasonable grasp. The German plan, however, was more ambitious than their opponents believed. Its aim was final and decisive success by complete defeat of the Allied Armies. The attack was designed first to separate them. by an overwhelming blow at this very point of junction, which in February 1918 was 30 miles further south of Cambrai than in December, then to roll the British Army right back on the coast and immobilise it there, and finally to turn on the French. Before America could put her levies in the field the Germans hoped that the catastrophes of the Armies and the demoralisation of the civil populations would compel the Allied Governments to accept a strong peace. Ludendorff's Staff appears to have believed that the close of the first day's fighting would see the British across the Somme, and the second day in general retreat down its lower valley. On the third day the pivot of the British line at Arras would fall, and before fresh reserves from the south could restore the situation, Haig's troops would be isolated and in disastrous retreat towards a precarious bridgehead on the Channel.
The German Staff had profited by the British tactics of secret assembly, absence of prolonged preparatory bombardment, and other features of our surprise attack at Cambrai, and had developed and perfected them by practice in Russia and Italy. Hitherto, with the partial exception of the Cambrai operation, the offensives on the Western front had been limited by the highly technical but rigid barrage, carried forward by which the assaulting infantry advanced with little or no impetus of its own. It was the weakness of these-tactics that they restricted the personal influence of commanders. Condemning them as narrow and sterile, Ludendorff replaced them by others calculated to yield more decisive results. Commanders, he laid down, were to command. Free play must be allowed for the fullest independence and tactical skill of subordinate leaders. The foremost infantry were to advance as long as possible and should be reinforced or "leap-frogged through" only when it became absolutely necessary. Attacking Divisions must be prepared not merely to pass the enemy artillery positions, but to press on the offensive for many miles and for several days. A feature which was to exercise immense importance was the insistence on the principle that reserves should not be thrown into the battle at points where the attack had been held up by centres of resistance and where unnecessary sacrifice was involved. They were to be used at points where the attack was still in movement, with a view to breaking down the enemy's resistance in the neighbouring sector by rolling it up from flank and rear. Hardly less important than this principle of infiltration was the novel application of machine guns, hitherto mainly regarded as defensive weapons, to the attack. The very framework of the new policy was the bold use of the light machine gun in the van of the advancing infantry and its employment on the basis of what had been conceived as infantry, rather than of machine gun, tactics.
Throughout the winter months the enemy's preponderance of forces enabled him to release a large number of his Divisions from trench duties. They were assiduously and intensively trained in the use of signal flares to indicate breaches in our line, in other features of the new methods of attack and in open warfare movements. They attained a very great technical proficiency. Their morale was of the highest. By the middle of March 46 fresh German Divisions were accumulated on the Western front, making a total of 192. Of these more than half lay opposite the British sector, and on the eve of the battle over 70 were massed against the Fifth and Third Armies. On the opening day of the attack, designated in felicitous encouragement to his soldiers as Michael's Day,{161} Ludendorff was to hurl against a front of 50 miles a force of splendidly trained soldiers, approximately equal in numbers to the entire population of New Zealand.
In anticipation of the German attack, the British Command in December had deliberately exchanged its offensive for a defensive policy. The change was reflected in the proportion of raids delivered by either side. Hitherto the number of the British raids had largely exceeded that of the German. Now twice as many were carried out on the British front by the enemy as by us, though the balance of successes was conspicuously in our favour. Immense efforts to improve defences were made along the whole line of 125 miles, extended since January down to the Oise, where Gough's Fifth Army, released from Flanders, replaced the French.
In gauging the point where the attack would be launched, the British Command had to consider 3 main possible courses of action open to the enemy. In the first place, the old attempt might be renewed in Flanders with the object of securing the Channel ports, immediately threatening England and severing direct communication with France. Again, an attack might be delivered in the central sector about Bethune with the primary purpose of breaking lateral communication, and with a secondary aim similar to, but on a larger scale than an operation in Flanders. Thirdly, they must consider the possibilities of that offensive in the south which Rawlinson had discussed, and which would have as its goal the separation of the French and British Armies with the capture of the railway centre at Amiens as a first objective. In the north and centre, where our hold of the Ypres and central ridges about Arras was shallow, little or no territory could be yielded, but in this southern portion of the line the area of the old battlefields might, if necessity constrained, be given up without serious consequences. Here also it was easier to bring up French reinforcements. Till indication of the enemy's plan developed, Sir Douglas Haig disposed his forces in accordance with these factors.
At the beginning of the year hostile activity continued, notably at Ypres. The enemy's ammunition and supply dumps had been augmented, and rail and road communications had been improved along the whole front. By the end of February, however, indications pointed unmistakably to the probability that the enemy's initial attempt would be made in the southern sector. While therefore the northern Armies were left sufficiently strong to meet emergencies, more than half the British effectives, together with the whole of the cavalry, were now at the disposal of the Fifth and Third Armies. Plans were drawn up with special regard to the reinforcement of this front by reserve Divisions from the rest of the British area. Owing to the great bend in the Allied line south of the Oise the German concentration menaced in almost equal degree the French front on the Aisne. Detailed arrangements, therefore, were made with the French for mutual support should the need arise.
Though the threatened fronts were strengthened as much as possible, the defence could not be regarded as thoroughly satisfactory. On the north, General Byng's Third Army, consisting from right to left of the V., IV., VI., and XVII. Corps, disposed 1 Division to nearly 3 miles of front, while General Gough's Fifth Army on the south, composed from right to left of the III., XVIII., XIX., and VII. Corps, had only 1 Division to 4 miles. On the other hand, it was hoped that the southernmost 10 miles on the Fifth Army front would be protected by the Oise marshes. Special measures were taken to construct a strong bridgehead at Péronne to cover the Somme crossings. In his defensive preparations Haig was hampered by the War Office's decision to retain large forces in England as a safeguard against the doubtful threat of invasion. Three zones of defence were, however, under construction. The third and final zone was in skeleton only. Nor was labour available to construct systems further in rear than on the average 4 to 5 miles behind the forward line of outposts. The 2 front systems were, however, strongly fortified, and the Staff, underestimating the German danger, believed them adequate to withstand the shock.
Against these thinly held and inadequately organised defences the German attack burst with unexpected power after a few hours of violently severe bombardment on the morning of 21st March. At least 60 Divisions were employed on a front of slightly over 50 miles. The British Intelligence Staff had predicted the launching of the attack on 20th or 21st March. Strenuous artillery counter-preparation had been carried out, and the garrisons of the different systems were all at their posts. Covered by a dense fog, the, enemy troops were enabled to reach within a few yards of our positions before they came under infantry fire. Our S.O.S. signals were masked in the fog, all communications were cut, and information of the attack reached our artillery and machine gun commanders late. The protective barrages were in consequence; delayed, and in frequent instances came down in rear of the assaulting Germans. In any case, all fire was largely masked by the fog. The swamps of the Oise, which it had been hoped would protect the extreme right flank, proved owing to unusually dry weather no serious obstacle.
In accordance with their new tactics the Germans drove with special strength on certain selected points and forced their way into our positions by sheer weight of numbers. Obstinate resistance inflicted extremely heavy losses and prevented that immediate and deep break-through on which Ludendorff had counted, but by the evening of the 21st the enemy had crossed the foremost defensive zone and penetrated into the second, before which the British Command had hoped definitely to arrest his progress. His furthest point of penetration was between 4 and 5 miles on the thinly-manned extreme right south-west of St. Quentin, and here, on the 22nd, the outnumbered and hard-pressed III. Corps, which had exhausted all local reserves, was thrown back behind its third and final defensive zone. The centre opposite St. Quentin was ordered to conform by withdrawing to the east bank of the Somme. The 2 northern Corps of the Fifth Army remained for the night east of the river, holding the important Péronne bridgehead and the third zone northwards to the Army boundary. The Third Army, repeatedly repulsing attacks, still clung desperately to its position in the rear trenches of the second belt, but during the night its right and centre were also brought back to the third zone.
On the morning of the 23rd, reluctant to accept battle with tired troops in the undeveloped Péronne bridgehead, General Gough took the "momentous" decision to abandon it and fall back west of the Somme. Thus his northern (VII.) Corps, crossing the river and retiring further, exposed the flank of the withdrawing V. Corps of the Third Army, and created a gap between the Armies. This gap the Germans exploited with remarkable swiftness, forcing the V. Corps back to the ridges immediately south-east of Bapaume. By the evening of the 23rd Ludendorff had advanced only 9 miles, reaching the objectives originally planned for the 21st, and our line was not yet broken. The British, however, had lost, besides other heavy casualties, 25,000 prisoners and 400 guns. The men, who had fought magnificently, were now exhausted, and over a large part of the front they were now behind all existing defence systems. British reserves alone could not. save the situation, and on the 23rd arrangements were made with the French, for the moment released from anxiety about Champagne, to take over the Fifth Army front south of the Somme.
At the junction of the Fifth and Third Armies the enemy pressure still continued on the 24th. Measures were taken to strengthen the VII. Corps, and the V. and IV. Corps on its left were ordered to fall back to a line across the old Somme battlefield west of Bapaume. This general line was taken up by midnight 24th/25th, but the withdrawal involved a loss of touch between the V. and IV. Corps which was eventually to affect the movements of the New Zealand Division. On the rest of the Fifth Army front the Somme was still held for some 8 miles south of Péronne, but beyond that point the enemy had made rapid progress and was in a position to threaten Noyon, which, with Nesle, fell into his hands on the following day.
The further developments south of the Somme, the attempt to sever the French and British Armies by an attack from Nesle, the advance of the Germans beyond Roye, the stand by General Carey's mixed force in the outer Amiens defences, the intervention of French reserves, the supersession of General Gough by General Rawlinson, the British resumption of command as far south as the Luce valley, the belated German effort at the Paris-Amiens railway, the final establishment of a stable Allied front in the first days of April, and with it the close of the German offensive on the Somme—all these are subject, matter of a larger history which can be studied nowhere better, despite inevitable reticences, than in the Commander-in-Chief's admirably lucid Despatch. It was with the right wing and the centre of the Third Army north of the river that the New Zealanders were summoned to play their part.
By the evening of the first day it was clear that the German attack involved practically the whole of Ludendorff's mass of manoeuvre. It was therefore "at once necessary and possible" to collect reserve Divisions from the rest of the front and hurry them to the Somme. In view of the vital importance of the First Army's position in the centre, its greater proximity to the battlefield and the distinct possibility of its becoming implicated, reinforcements were drawn principally from General Plumer's Second Army further north. Among the troops so called on was the New Zealand Division.
Their period of rest and training in the Staple area was favoured by exceptionally fine weather, under which health and general fitness rapidly recovered from the strain of the winter. A comprehensive scheme of recreational training utilised the men's characteristic fondness of and aptitude for sports and competitions, with the object of promoting physical vigour, developing the fighting spirit, stimulating mental as well as physical alertness and restoring the vitality inevitably affected by a long period in the trenches. In the general military training it is interesting to note that stress was laid on the use of infantry weapons in combination with machine guns and light mortars, and on the development of the initiative and power of leadership of section and platoon commanders, especially as regards use of ground, direction and control of fire, and quickness of decision in dealing with all the varied situations which arise in battle. Rehearsals were made of deliberate fire-covered withdrawals from advanced positions both by day and by night, and of taking over in obscure situations defences held by a mixture of various and disorganised units. Suggestive, too, was the insistence given to emphasising in talks to the men the marked superiority, now long and indisputably established, of the New Zealand soldier over the enemy in any kind of fighting. It had been intended that each infantry brigade should have a training period of 4 weeks, 1 brigade at a time remaining in the forward area for work on the Corps defence system. Musketry was practised on the ranges at Moulle beyond St. Omer. By the middle of March rest and training had reforged the Division into a weapon of sterling quality.
In view of the expected offensive, arrangements had been made for rapid movement in case of emergency to the Ypres ridges. On 21st March, however, when the German attack broke out on the Somme, orders were received that the Division would pass from Corps into Army reserve and be held ready to entrain for the south after midnight 22nd/23rd March. Provision was made for the relief of the artillery from the line and for the concentration in the Divisional area of the 4 battalions training on the rifle ranges at Moulle. On the 22nd the Division was marked for transfer to the Third Army and ordered to commence entrainment on the afternoon of the 24th. On that date the various units in the Staple area marched to the stations at Cassel and Caestre. The Rifle Brigade{162} group, with the Headquarters and 2 companies of the Engineers and with the Pioneer Battalion, all then in the forward area at Ypres, concentrated at Hopoutre, near Poperinghe. The artillery, completing their relief behind Westhoek Ridge on 23rd March, entrained on the 25th at Caestre, Godewaersvelde and Hopoutre. The rate of entraining was somewhat retarded owing to the destruction of a railway bridge near St. Pol by hostile action, and consequent disorganisation of the railway system. Caestre was bombed by aeroplanes, but no hitch marred the general arrangements. The Division for the remainder of its history was not again to form part of the XXII. Corps.
By this time the British Staff anticipated an extension of the attack to the northern flank about Arras. It was at first intended, therefore, that the Division should on arrival in the Third Army area come under the command of the XVII. Corps on General Byng's left. The time for this German move, however, had not yet come, and owing to urgent need of further reserves on the Fifth Army front this order was changed on the 24th. The Division was then diverted further south to the Bray area on the Somme, where it would be in general reserve and be prepared to move at 4 hours' notice. It was allotted meantime to the VII. Corps on the left of the Fifth Army, and General Russell on arrival established his headquarters with the VII. Corps Commander at Corbie.