The Battle of Langemarck (16–18 August 1917) was the second Anglo-French general attack of the Third Battle of Ypres, during the First World War. The battle took place near Ypres in Belgian Flanders, on the Western Front against the German 4th Army. The French First Army had a big success on the northern flank from Bixschoote to Drie Grachten (Three Canals) and the British gained a substantial amount of ground northwards from St Julien to the boundary with the French.

The attack on the Gheluvelt Plateau on the right (southern) flank captured a considerable amount of ground but failed to reach its objectives. German counter-attacks recaptured most of the lost territory during the afternoon. The weather prevented much of the British programme of air co-operation with the infantry, which had made it easier for German reserves to assemble on the battlefield.

An unusually large amount of rain in August, poor drainage and lack of evaporation turned the ground into a morass, which was worse for the British and French, who occupied lower-lying ground and attacked areas which had been frequently and severely bombarded. Mud and flooded shell holes severely reduced the mobility of the infantry and poor visibility hampered artillery observers and the crews of artillery-observation aircraft. Rainstorms and the costly German defensive success during the rest of August, led the British to stop the offensive for three weeks.

In early September, the sun came out and with the return of a breeze, dried much of the ground. The British rebuilt roads and tracks to the front line, transferred more artillery and fresh divisions from the armies further south and revised further their tactics. The main offensive effort was shifted southwards and led to success on the Gheluvelt Plateau at the Battle of the Menin Road Ridge (20–25 September), the Battle of Polygon Wood (26 September – 3 October) and the Battle of Broodseinde (4 October), before the autumn rains began.

Background

Strategic background

Artillery preparation for the Second Battle of Verdun, in support of the Allied offensive in Flanders, which had been delayed from mid-July began on 20 August, after an eight-day bombardment. Attacking on an front, the French captured Mort Homme, Hill 304 and The 5th Army could not counter-attack because its divisions had been sent to Flanders. Fighting at Verdun continued into September, adding to the pressure on the German army. The Canadian Corps fought the Battle of Hill 70 outside Lens on the British First Army front. The attack was costly but inflicted great losses on five German divisions and pinned down troops reserved for relief of tired divisions on the Flanders front. The strategy of forcing the German army to defend the Ypres salient, to protect the Belgian hinterland, the coast, railways and submarine bases, had succeeded. The French and Russians could make local attacks but needed more time to recuperate free of big German attacks. The British had forced the Germans into a costly defensive battle but the Fifth Army (General Hubert Gough) had struggled to advance since 31 July, due to the tenacity of the German defence and the unusually wet weather. Gough kept pressure on the 4th Army, to prevent the Germans from recovering and to enable Operation Hush on the coast, which needed the high tides due at the end of August.

Tactical developments

On 31 July 1917, Field Marshal Sir Douglas Haig had begun the Third Battle of Ypres, to inflict unsustainable losses on the German army and to advance out of the Ypres Salient to capture the Belgian coast and end the submarine threat from Belgian bases to the southern North Sea and the Dover Straits. At the Battle of Messines Ridge (7–14 June) the ridge had been captured down to the Oosttaverne line and a substantial success had been gained at the Battle of Pilckem Ridge (31 July – 2 August). Ground conditions in August were poor, as the surface had been bombarded, fought over and partially flooded, at times severely so. Shelling had destroyed drainage canals in the area and the unseasonable heavy rain in August turned parts into morasses of mud and waterlogged shell-craters. Supply troops walked to the front on duck boards laid across the mud; carrying loads of up to they could slip into the craters and drown. Trees were reduced to blasted trunks, the branches and leaves torn away and corpses from earlier fighting were uncovered by the rain and shelling. The ground was powdery to a depth of and when wet had the consistency of porridge.

Brigadier-General John Davidson, Director of Operations at BEF HQ, submitted a memorandum on 1 August, urging caution on Haig and Gough. Davidson recommended that the preliminary operation by II Corps not be hurried; a full artillery preparation and a relief by fresh divisions should be completed before the operation because tired and depleted units had often failed in such attacks. Two fresh divisions were sent to II Corps and two or three clear days would be needed for accurate artillery-fire, especially as captured ground on the Gheluvelt plateau gave better observation. Captured German maps revealed the positions of their machine-gun emplacements which, being small and concealed, needed accurate fire by the artillery to destroy them. The capture of the black line, from Inverness Copse north to Westhoek, would be insufficient to protect an advance from the Steenbeek further north and large German counter-attacks could be expected on the plateau, given that it was the German defensive point of main effort ().

Weather Except where shell-holes obstructed drainage, the ground in west Flanders dried quickly and became dusty after a few dry days. A 1989 study of weather data recorded from 1867 to 1916 at Lille, down the road from Ypres, showed August to be more often dry than wet, that there was a trend towards dry autumns (September–November) and that average rainfall in October had decreased over the previous fifty years. From 1 to 10 August, of rain fell, including in a thunderstorm on 8 August. During August 1917, of rain fell, of which fell on The month was so overcast and windless that water on the ground dried slower than usual. September had of rain and was much sunnier, the ground drying quickly, hard enough in places for shells to ricochet and for dust to blow in the breeze. In October, of rain fell, compared to the 1914–1916 average of and from there was another of rain and only nine hours of sunshine, little of the water drying; another of rain fell on 10 November.

Prelude

British preparations

Few of the pillboxes captured on 31 July had been damaged by artillery-fire. Before the attack, Brigadier-General Ambrose Ricardo, the 109th Brigade, [36th (Ulster) Division], commander, arranged three-minute bombardments on selected pillboxes and blockhouses by the XIX Corps heavy artillery, with pauses so that artillery observers could make corrections to contradictory maps and photographs. It was discovered that on many of the targets, the shell dispersion covered hundreds of yards, as did wire-cutting bombardments. On 2 August, at the suggestion of Brigadier-General Hugh Elles, commander of the Tank Corps, it was decided that the surviving tanks were to be held back due to the weather, for use en masse later on, although some were used later in the month. The preliminary operation intended for 2 August was delayed by rain until 10 August and more rain delays forced the postponement of the general offensive from 4 to 15 August and then again to 16 August.

The 20th (Light) Division replaced the 38th (Welsh) Division on 5 August. The 7th Battalion of the Somerset Light Infantry took over captured German trenches behind the front line on 5 August, which had been turned into the British reserve line and lost three men to shellfire while waiting for dark. On arrival at the support line forward and the front line beyond, the battalion found that the front line consisted of shell hole posts with muddy bottoms strung along the Steenbeek, from the Langemarck road to the Ypres–Staden railway. British artillery was engaged in destructive bombardments of the German positions opposite and German artillery fire was aimed at the British infantry concentrating for the next attack. After heavy rain all night, the battalion spent 6 August soaked through and had two men being killed. On 7 August, there were , including twelve killed before the battalion was relieved until 14 August. Training began for the next attack, planned from trench maps and aerial photographs. Each company formed three platoons, two for the advance, with two rifle sections in the lead, the Lewis-gun sections behind and the third platoon to mop up.

Training emphasised the need for units to "hug" the creeping barrage and to form offensive flanks, to assist neighbouring troops whose advance had been halted by the defenders. Infantry that got forward could provide enfilade fire and envelop German positions, which were to be left behind and mopped-up by reserve platoons. Every known German position was allocated to a unit of the left in the battalion, to reduce the risk of unseen German positions being overrun and the occupants firing at the leading troops from behind. While the Somersets were out of the line, the 10th and 11th battalions, the Rifle Brigade edged forward about beyond the Steenbeek, which cost the 10th Battalion On 15 August an attempt to re-capture the Au Bon Gite blockhouse, beyond the Steenbeek, which had been lost to a German counter-attack on 31 July, failed. It was decided that the infantry for the general attack, due on 16 August, would have to squeeze into the ground beyond the river in front of the blockhouse for the attack on Langemarck.

Operation Summer Night

Operation Summer Night () was a German methodical counter-attack () near Hollebeke in the Second Army area on the southern flank, which began at on 5 August. The 22nd Reserve Division had been relieved by the 12th Division and the 207th Division after its losses on 31 July. After a short bombardment, three companies of I Battalion, Infantry Regiment 62 of the 12th Division captured a slight rise north-east of Hollebeke, surprising the British, who fell back . The new German positions were on higher and drier ground and deprived the British of observation over the German rear, reducing casualties from British artillery-fire.

Further to the south, Reserve Infantry Regiment 209 (RIR 209) and Reserve Infantry Regiment 213 (RIR 213) of the 207th Division attacked Hollebeke through thick fog and captured the village, despite many casualties, taking at least Most of the British were in captured pillboxes and blockhouses, which had to be attacked one by one. At three signal flares were fired to indicate success. The Germans later abandoned Hollebeke and reoccupied the old A line, then withdrew to their start line because of the severity of British counter-attacks and artillery-fire. left the front-line ragged, with a gap between RIR 209 and RIR 213, which the British tried to exploit with attacks and counter-attacks, before the bigger British effort of 10 August against the Gheluvelt Plateau.

Capture of Westhoek