The important changes which were to take place in this area during the next six weeks are so material to the development of the Campaign of 1917 that it is necessary to review briefly the operations which were being conducted further south. The termination of the battles of the Somme in November 1916 had left the enemy in possession of the whole of the Ancre Valley from Le Transloy to Grandcourt and of excellent positions on the high ground immediately north of Beaumont-Hamel; while in rear of this position he had made great progress in the construction of two more lines of defence running in a direction from north-west to south-east about Bapaume.
The advance of our troops over the Thiepval-Morval Ridge had, however, left him confined in a marked salient, of which the apex was Gommecourt Wood, between the Ancre on the south and the Scarpe where it passes Arras on the north; and conditions appeared very favourable for improving our situation in the neighbourhood of Beaumont-Hamel before the conditions of winter should render active operations on a large scale impossible. Accordingly operations which met with immediate success were reopened on the 18th November on the left bank of the Ancre between Grandcourt and Pys. These were renewed in January in the Beaucourt valley on the opposite side of the river with such marked success that the enemy was compelled to relinquish his hold on the high ground north of Beaumont-Hamel while his position in Grandcourt became precarious in the extreme.
On the night of the 5th/6th February 1917 Grandcourt was evacuated and the enemy fell back to the line Serre-Miraumont-Pys. Attacks with which these initial successes were followed up on the 17th and 18th February secured to the British complete command over the enemy's defences of the upper Ancre and Miraumont village, while they accentuated his salient west of Serre. The loss of this would lay open for us a further advance on Puisieux-au-Mont and render the defence of the Gommecourt Salient exceedingly hazardous. It was therefore to be expected that any further withdrawal on the part of the enemy from in front of Miraumont would entail a withdrawal on a large scale, and this actually occurred.
By the 24th February British troops had occupied Serre and all the enemy's defences on a line from that village to Gueudecourt, a frontage of some nine miles. On the 27th February patrols entered Gommecourt park and village, the prize so desperately fought for and withheld from the 1/4th Battalion six months earlier, and the following morning the whole of Puisieux fell into our hands. On the right the enemy's resistance was more stubborn, but an assault on Irles on the 10th March, which proved entirely successful, brought us face to face with the first of the two lines of defence about Bapaume to which reference has already been made. But even here the enemy made no determined stand, and by the 13th our pursuing columns were making preparations to assault the rear line.
The German Retirement, February-March, 1917
The situation, therefore, when the 2/4th Battalion returned to the line after its rest, the last two days of which were spent at Gaudiempré, was that Corps and Divisional staffs were eagerly seeking information as to any indication of the enemy's expected retirement between Arras and Monchy-au-Bois, this being the only sector between Arras and the Somme now left in his possession, which he had held at the end of the Somme operations. This entailed a heavily increased burden of night patrolling duties on all troops in the line.