By these attacks, says Sir Douglas Haig, it was expected that the important German forces opposite the French and Americans would be pressed back upon the difficult country of the Ardennes while the British thrust at their main communications.
The long continued blows delivered by the British Armies, although enormously successful, had placed a great strain on the troops, and their losses, though small in proportion to the enemy's and to the results achieved, were in the aggregate considerable. The Hindenburg positions were known to be strongly defended, and an unsuccessful attack on them would have a serious political effect and inevitably revive the declining German morale. An important crisis in the War had been reached and it was essential that the success of the British in this new attack should be decisive. After weighing the various considerations involved Sir Douglas Haig states:
... I was convinced that the British attack was the essential part of the general scheme and that the moment was favourable. Accordingly I decided to proceed with the attack....
The battle, which opened on the British front on the 27th September (Battle of Cambrai, 1918), culminated on the 5th October in the capture of all the Hindenburg trenches and of such isolated trench systems as lay in rear of it.
The part of the 56th Division in this great battle was the crossing of the Canal du Nord. This strong natural obstacle was considered to be too stubbornly held to yield to frontal attack on a wide area; and the general plan was therefore for the Canadian Corps to cross it on a narrow front north of Mœuvres and then spreading out fanwise to extend the gains north and south on the east bank.
The 1st Canadian Division, on the left of the Canadian Corps and adjoining the right of the 56th Division, was to cross the Canal south of the Arras-Cambrai Road and carry the line forward to Haynecourt. After this the 56th Division, astride the Canal on a front as far east as Sauchicourt Farm, with the 11th Division on its right, would attack northwards towards Oisy-le-Verger and the Sensée River at Palluel.
The 56th Division attack was entrusted east of the Canal to the 169th Brigade and west of it to the Kensingtons of the 168th Brigade. The London Scottish and 1/4th Londons in line had thus the peculiar experience of the attack actually crossing their front from right to left.
At 5.30 a.m. on the 27th September the crash of the barrage announced the opening of the Canadian Corps attack. The enemy's retaliation was slight and had practically ceased by 6 a.m. The 1/4th Londons' area was occupied by eight brigades of field guns engaged in firing a flank barrage to the main attack until 2.48 p.m., when they were to switch on a creeping barrage for the attack northwards along the Canal. Additional flank protection was furnished by six companies of machine-guns also in our area. In view of this heavy barrage and the possibility of severe retaliation the 1/4th Londons' outpost line was thinned out to two platoons in charge of Lieut. T. R. Fletcher, the remainder of the front companies being withdrawn to the support position.
The Canadian attack went well, but very stiff opposition was encountered in Marquion, so that the 56th Division attack from the Blue line had to be postponed from 2.48 p.m. to 3.28 p.m. Excellent work was done by the 512th and 513th Field Companies, R.E. (56th Division), in bridging the Canal at Marquion.
During the morning the 1/4th Londons' front seemed to be clear, and an officer's patrol under 2/Lieut. O. C. Hudson was sent forward to reconnoitre the enemy positions along the Agache River, which were found to be unoccupied.