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 The Gheluvelt Plateau became a sea of mud, flooded shell craters, fallen trees and barbed wire. Troops were exhausted quickly by the weather, massed artillery bombardments and lack of food and water. The rapid relief of units spread the exhaustion through all the infantry, despite the front being held by fresh divisions. British artillery fired a preparatory bombardment from Polygon Wood to Langemarck but the German guns concentrated on the Plateau. The British gunners were hampered by low cloud and rain, which made air observation extremely difficult and shells were wasted on empty gun emplacements. The British 25th Division, 18th (Eastern) Division and the German 54th Division had relieved the original divisions by 4 August but the German 52nd Reserve Division was left in the line. By 10 August the infantry on both sides of no man's land were exhausted. The 18th (Eastern) Division attacked on the right; some troops quickly reaching their objectives but German artillery isolated them around Inverness Copse and Glencorse Wood. German troops counter-attacked several times and by nightfall the Copse and all but the north-west corner of Glencorse Wood had been recaptured. The 25th Division on the left flank advanced quickly and reached its objectives by rushing the Germans in Westhoek. Snipers and attacks by German aircraft caused an increasing number of casualties; the Germans counter-attacked into the night and the British guns bombarded German troops in their assembly positions. The appalling weather and costly defeats caused a slump in the morale of the British infantry; lack of replacements began to concern the German commanders.
Plan The attack was planned as an advance in stages, to keep the infantry well under the protection of the field artillery. II Corps was to reach the green line of 31 July, an advance of about and form a defensive flank from Stirling Castle to Black Watch Corner. The deeper objective was compensated for by reducing battalion frontages from and leap-frogging supporting battalions through an intermediate line, to take the final objective. On the
56th (1/1st London) Division front, the final objective was about into Polygon Wood. On the right, the
53rd Brigade of the 18th (Eastern) Division was to advance from Stirling Castle, through Inverness Copse to Black Watch Corner, at the south-west corner of Polygon Wood, to form a defensive flank to the south. Further north, the
169th Brigade was to advance to Polygon Wood through Glencorse Wood and
167th Brigade was to reach the north-western part of Polygon Wood through Nonne Bosschen. The 8th Division was to attack with two brigades between Westhoek and the Ypres–Roulers railway, to reach the green line on the rise east of the Hanebeek stream. Eight tanks were allotted to II Corps to assist the infantry. The artillery support for the attack was the same as that for 10 August, guns for the creeping barrage moving at in five minutes, with howitzers and placing standing barrages beyond the final objective. Eight machine-gun companies were to fire barrages on the area from the north-east of Polygon Wood to west of Zonnebeke. XIX and XVIII corps, further north, had also to capture the green line, slightly beyond the German (third position). Each XIX Corps division had fourteen batteries for the creeping barrage, howitzer batteries and forty machine-guns for standing barrages, along with the normal heavy artillery groups. Each division also had a hundred and eight 18-pounders and howitzers for bombardment and benefited from supply routes which had been far less heavily shelled than those further south. In the XVIII Corps area, a brigade each from the 48th (South Midland) Division and 11th (Northern) Division with eight tanks each, was to attack from the north end of St Julien to the White House east of Langemarck. The 20th (Light) Division planned to capture Langemarck with the
60th Brigade and
61st Brigade. The
59th Brigade was to go into reserve after holding the line before the attack, less the two battalions in the front line, which were to screen the assembly of the attacking brigades. The attack was to begin on the east bank of the Steenbeek, where the troops had of room to assemble, crossing over on wooden bridges laid by the engineers the night before the attack. The first objective (blue line), was set on a road running along the west side of Langemarck, the second objective (green line) was further on, at the east side of the village and the final objective (red line) was another ahead, in the German defences beyond Schreiboom. On the right, the 60th Brigade was to attack on a one-battalion front, with two battalions to leapfrog through the leading battalion, to reach the second and final objectives. The attack was to move north-east behind Langemarck, to confront an expected German counter-attack up the road from Poelcappelle, away, while the 61st Brigade, attacking on a two-brigade front, took the village shielded by the 60th Brigade. The manoeuvre of the 60th Brigade would also threaten the Germans in Langemarck with encirclement. Au Bon Gite, the German blockhouse which had resisted earlier attacks, was to be dealt with by infantry from one of the covering battalions and a Royal Engineer Field Company. Artillery for the attack came from the 20th (Light) Division, 38th (Welsh) Division and the heavy guns of XIV Corps. A creeping barrage was to move at in four minutes and a standing barrage was to fall on the objective lines in succession as the infantry advanced. The first objective was to be bombarded for twenty minutes, as the creeping barrage moved towards it, then the second objective was to be shelled for an hour to catch retreating German soldiers, destroy defences and force any remaining Germans under cover. A third barrage was to come from the XIV Corps heavy artillery, sweeping back and forth with high explosive, from ahead of the foremost British troops, to stop German machine-gunners in retired positions from firing through the British barrage. Smoke shell was to be fired to hide the attacking troops, as they re-organised at each objective. A machine-gun barrage from was arranged, with half of the guns moving forward with the infantry, to add to their firepower. German troops were also to be
strafed by British aircraft from low altitude. The French First Army was to extend the attack north, from the Kortebeek to Drie Grachten, aiming to reach the St Jansbeck.
German defences The German 4th Army operation order for the defensive battle was issued on 27 June. German infantry units had been reorganised on similar lines to the British, with a rifle section, assault troop section, a grenade-launcher section and a light machine-gun section. Field artillery in the divisions had been organised into artillery assault groups, which followed the infantry to engage the attackers with observed or direct fire. Each infantry regiment of the 183rd Division, based around Westroosebeke behind the northern flank of (Group Ypres), had a battalion of the divisional field artillery regiment attached. From mid-1917, the area east of Ypres was defended by six German defensive positions: the front position, (second position), (third position), (fourth position), (fifth position) and (under construction). Between the German positions were the Belgian villages of
Zonnebeke and Passchendaele. On 31 July, the German
defence in depth had begun with a front system of three breastworks: each about apart, garrisoned by the four companies of each front battalion, with listening-posts in no-man's-land. About behind these works was the (artillery protective line), the rear boundary of the forward battle zone (). Companies of the support battalions, ( security detachments () to hold the strong-points and storm troops [] to counter-attack towards them), were placed at the back of the , half in the pill-boxes of the , to provide a framework for the re-establishment of defence-in-depth, once the enemy attack had been repulsed. Dispersed in front of the line were divisional sharpshooter () machine-gun nests called the strongpoint line (). Much of the north of the Ypres–Roulers railway, had fallen on 31 July. The (second position) roughly corresponded to the British black line (second objective) of 31 July, much of which had been captured, except on the Gheluvelt Plateau. The line marked the front of the main battle zone (), which was about deep, behind which was the (third position) and most of the field artillery of the front divisions. In pillboxes of the were the reserve battalions of the front-line regiments. The leading regiment of an division was to advance into the zone of the front division, with its other two regiments moving forward in close support from support and reserve assembly areas, further back in the . divisions were accommodated behind the front line and at the beginning of an attack began their advance to assembly areas in the behind , ready to intervene in the , for (the instant-immediate counter-thrust). Opposite the French First Army (), the Germans had counter-flooded the area between
Dixmude and Bixschoote and fortified the drier ground around the waters to stop an attack across or around the floods. Drie Grachten (Three Canals) was the main German defensive fortification in the area, blocking the Noordschoote–Luyghem road at the crossing of the Yperlee Canal north of the Steenbeek. The area was beyond the confluence with the Kortebeek, where the rivers joined to become the St Jansbeek. From Luyghem, a road ran south-east to Verbrandemis and the road from Zudyschoote and Lizenie to Dixmude crossed the Yperlee at Steenstraat. The capture of Luyghem, Merckem and the road would threaten Houthoulst Forest, to the south of Dixmude and north of Langemarck. By 15 August, the French had closed up to Drie Grachten from Bixschoote to the south-east and Noordschoote to the south-west. West of the Yperlee Canal, the bridgehead consisted of a semi-circular breastwork due to waterlogged soil. Reinforced concrete shelters were connected by a raised trench of concrete, earth and
fascines, with a communication trench leading back to a command post. Several hundred yards along a communication trench on the north side of the road was a small blockhouse. Barbed wire entanglements had been laid above and below the water in front of the post and blockhouse astride the Noordschoote–Luyghem road. To the north was (the sluice) Redoubt and another pillbox lay to the south, on the west side of the Yperlee. The redoubts corresponded to the defences on the east bank of the canal and enclosed the flanks of the position above the inundations. Platforms gave machine-guns command of a wide arc of ground in front. On the east bank of the Yperlee was a rampart of reinforced concrete, behind and parallel with the canal, from opposite to the southern redoubt. Communication between the rampart and the defences of the Luyghem peninsula was via the raised road from Drie Grachten to Luyghem and two footbridges through the floods, one north and one south of the road. Every , were traverses with reinforced concrete shelters. In an appreciation of 2 August, correctly identified the as the British objective on 31 July and predicted more attacks on the Gheluvelt Plateau and further north towards Langemarck. In the area, only the 3rd and 79th Reserve divisions remained battleworthy, the other four having suffered On 4 August, a assessment concluded that the British needed to force back the 52nd Division on the Gheluvelt Plateau, where the defensive scheme had the front regiment of each division backed by the other two regiments in support and in reserve behind the front line. Crown Prince Rupprecht expressed concern on 5 August, that the weather conditions were rapidly exhausting the German infantry. Casualties were about per division, lower than the average of on the Somme in 1916 but only because divisions were being relieved more frequently. Supplying troops in the front line was extremely difficult because the British were using more gas, which caught carrying parties by surprise; the 6th Bavarian Reserve Division had suffered casualties. ==Battle==