Battle of Polygon Wood - Background

Background

The preliminary operation to capture Messines ridge 7–14 June had been followed by a strategic pause as the British repaired their communications behind Messines ridge, completed the building of the infrastructure necessary for a much larger force in the Ypres area and moved troops and equipment north from the Arras front. After delays caused by local conditions, the Battles of Ypres had begun on 31 July with the Battle of Pilckem ridge, which was a substantial local success for the British, taking a large amount of ground and inflicting many casualties on the German defenders. The German defence had nonetheless recovered some of the lost ground in the middle of the attack front and restricted the British advance on the Gheluvelt plateau further south. British attacks had then been seriously hampered by unseasonal heavy rain during August and had not been able to retain much of the additional ground captured on the plateau on 10, 16–18, 22–24 and 27 August due to the determined German defence, mud and poor visibility.

Sir Douglas Haig ordered artillery to be transferred from the southern flank of the Second Army and more artillery to be brought into Flanders from the armies further south, to increase the weight of the attack on the Gheluvelt plateau. The principal role was changed from the Fifth to the Second Army and the boundary between the Second and Fifth armies was moved north towards the Ypres – Roulers railway, to narrow the frontages of the Second Army divisions in the area. A pause to reorganise and to improve supply routes behind the front line, to carry ammunition (54,572 tons (49,506,627 kg) above normal expenditure) to gun positions advanced onto captured ground and for the infantry and artillery reinforcements to arrive and practice for the next attack, took place as the rains stopped and the ground began to dry, a delay which misled the Germans, who risked moving some units away from Flanders. The offensive had resumed on 20 September, using similar step-by-step methods to those of the Fifth Army after 31 July, with a further evolution of technique based on the greater mass of artillery made available, to enable the consolidation of captured ground with sufficient strength and organisation to defeat German counter-attacks. The Battle of the Menin Road ridge had seen most of the British objectives captured and held, with substantial losses being inflicted on the six German ground-holding divisions and their three supporting Eingreif divisions. British preparations for the next step began immediately and both sides studied the effect of the battle and the implications it had for their intentions.