Battle of Pilckem Ridge

The Battle of Pilckem Ridge, 31 July – 2 August 1917, was the opening attack of the main part of the Third Battle of Ypres in the First World War. The battle took place in the Ypres Salient area of the Western Front. The Allied attack had mixed results; a substantial amount of ground was captured and a large number of casualties inflicted on the German defenders, except on the tactically vital Gheluvelt plateau on the right flank. The German defenders also recaptured some ground on the XIX Corps front, from the Ypres–Roulers railway, north to St. Julien. After several weeks of changeable weather, heavy rainfall began in the afternoon of 31 July and had a serious effect on operations in August, causing more problems for the British who were advancing into the area devastated by artillery fire and which was partly flooded. The battle became controversial, with disputes about the predictability of the August deluges and for its mixed results, which in much British writing were blamed on misunderstandings between Gough and Haig and on faulty planning, rather than on the resilience of the German defence.

Strategic background
Operations in Flanders, Belgium had been desired by the British Cabinet, Admiralty and War Office since 1914. Douglas Haig succeeded John French as Commander-in-Chief of the British Expeditionary Force on 19 December 1915. A week after his appointment, Haig met Vice-Admiral Reginald Bacon, who emphasised the importance of obtaining control of the Belgian coast, to end the threat from German naval forces based in Bruges. In January 1916, Haig ordered General Henry Rawlinson to plan an attack in the Ypres Salient. The need to support the French army during the Battle of Verdun 21 February – 18 December 1916 and the demands of the Somme battles 1 July – 18 November 1916, absorbed the British Expeditionary Force's offensive capacity for the rest of the year.

On 22 November Haig, Chief of the Imperial General Staff William Robertson, First Sea Lord Admiral Henry Jackson and Dover Patrol commander Vice-Admiral Reginald Bacon, wrote to General Joffre urging that the Flanders operation be undertaken in 1917, which Joffre accepted. In late 1916 and early 1917, military leaders in Britain and France were optimistic that the casualties they had inflicted on the German army at the Battle of Verdun, the Battle of the Somme and on the Eastern Front had brought the German army close to exhaustion, although the effort had been immensely costly. At the conference in Chantilly in November 1916 and a series of subsequent meetings, the Entente agreed on an offensive strategy to overwhelm the Central Powers by means of simultaneous attacks on the Western, Eastern and Italian Fronts.

The Prime Minister David Lloyd George, sought to limit British casualties and proposed an offensive on the Italian front. British and French artillery would be transferred to Italy to add weight to the offensive. This suggestion was opposed by the French and Italian delegations and the British General Staff, at least covertly and was discarded. The new French Commander-in-Chief, Robert Nivelle, believed that a concentrated attack by French forces on the Western Front during the spring of 1917, could break the German front and lead to a decisive victory. Nivelle's plan was welcomed by the British, despite many in the Cabinet and War Office being sceptical. A French attack would mean a lesser burden falling on the British. Haig was ordered to co-operate with Nivelle's plan but secured Nivelle's agreement that in the event the Nivelle Offensive failed, the British would attack in Flanders with French support.

On 9 April 1917 British and Empire forces undertook a preliminary attack at Arras and the Nivelle Offensive began on 16 April. The French attack gained ground at great cost but no breakthrough leading to open warfare and the decisive defeat of the German army occurred, leading to Nivelle's replacement by Philippe Petain, a collapse in morale and mutinies in the French armies. While the French recuperated, offensive action on the Western front could only come from the British Expeditionary Force. It was not until June 1917, that the principle of a Flanders campaign was approved by the British Cabinet and more grudgingly by the Prime Minister, against his preference for an Italian campaign.

British plans 1916–1917
Haig ordered General Herbert Plumer, the commander of the British Second Army which occupied the Ypres Salient, to produce a plan in late 1916. Haig was dissatisfied with the limited scope of Plumer's plan for the capture of Messines Ridge and Pilckem Ridge. By early 1917 Haig felt that Nivelle's ambitious attempt at a decisive battle, would either force the Germans to abandon the Belgian coast or that the German Fourth Army in Flanders would have divisions taken away, to replace losses further south. Plumer produced a revised plan, in which in the first stage, Messines and Pilckem ridges would be captured, with an advance some distance onto the Gheluvelt Plateau, soon afterwards an attack would be made across the Gheluvelt Plateau, to Passchendaele and beyond. Plumer believed that a force of 35 divisions and 5,000 guns would be necessary, which was far beyond the amount of artillery in the British Expeditionary Force.

Haig also asked for an assessment from Colonel Macmullen on his headquarters staff, who proposed that the Gheluvelt Plateau be taken by a massed tank attack, reducing the need for artillery. In April, a reconnaissance by Captain Giffard LeQuesne Martel found that the area was unsuitable for tanks, because of narrow defiles between the three woods obstructing the approaches, the broken state of the ground and woods on the high ground. The tanks would have to detour north of Bellewaarde lake to Westhoek then wheel right at the German Albrecht (second) line. Plumer produced a second revision of his plan; Messines Ridge and the west end of the Gheluvelt Plateau would be attacked first and then Pilckem Ridge a short while later. The British Fourth Army commander, General Rawlinson proposed a plan to take Messines Ridge, then the Gheluvelt Plateau and Pilckem Ridge within 47–72 hours.

On 14 February after discussions with Rawlinson, Plumer and Haig, Macmullen submitted a memorandum which became the "GHQ 1917" plan. On 7 May, Haig set the timetable for the preliminary attack on Messines ridge (7 June) and the Flanders offensive some weeks later. A week after the Battle of Messines Ridge, Haig informed is his Army commanders that his objectives were to wear down the German army, secure the Belgian coast and connect with the Dutch frontier by capturing Passchendaele ridge and advancing on Roulers and Thourout, to cut the railway supplying the German garrisons holding the Western Front north of Ypres and the Belgian coast. An attack by the Fourth Army would then begin on the coast, combined with an amphibious landing (Operation Hush) in support of the main advance to the Dutch frontier. On 13 May Haig appointed General Hubert Gough to the command of the Ypres operation and the coastal force and Macmullen gave Gough the "GHQ 1917" plan the next day.

British offensive preparations


Gough held meetings with his Corps commanders on 6 and 16 June where the third objective of the "GHQ 1917" plan, which included the German Wilhelm (third) Line, was added to the first and second objectives to be taken on the first day. A fourth objective was also given for the first day but was only to be attempted opportunistically, in places where the German defence had collapsed. Gough intended to use five divisions from the Second Army, nine divisions and one brigade from the Fifth Army and two divisions from the French First Army. Gough planned a preparatory bombardment from 16–25 July. The Second Army was to create the impression of a more ambitious attack beyond Messines ridge, by capturing outposts in the Warneton line. The Fifth Army was to attack along a front of approximately 14000 yd, running from Klein Zillebecke in the south to the Ypres–Staden railway in the north, with the French First Army on the northern flank attacking with two divisions, from the boundary with the British XIV Corps north to the flooded area just beyond Steenstraat. The infantry trained on a replica of the German trench system, built using information from aerial photographs and trench raids. Specialist platoons were given additional training on methods to destroy German pillboxes and blockhouses.

The attack was not a breakthrough attempt, the fourth German defensive position Flandern I, lay 10000 – behind the front line, well beyond the fourth objective (red line). Behind Flandern I was Flandern II, with Flandern III under construction. In his Operation Order of 27 June to the Fifth Army corps commanders, Gough gave the green line as the main objective. Advances towards the red line, (fourth objective) were to be made by patrols of fresh troops, to take vacant ground that was tactically valuable, exploiting any German disorganisation in the first 24 hours. The Fifth Army plan was more ambitious than Plumer's version, which had involved a shallower advance of 1000 – on the first day. Major-General J. Davidson, Director of Operations at General Headquarters expressed concern that there was "ambiguity as to what was meant by a step-by-step attack with limited objectives" and suggested reverting to an advance of no more than 1500 –, to increase the concentration of British artillery. Gough's reply stressed the need to plan for opportunities to take ground left temporarily undefended and that this was more likely in the first attack, which would have the benefit of long preparation. After discussions at the end of June, Haig endorsed Gough's plan, as did Plumer the Second Army commander.

The intended slow build-up of Allied air activity over the Ypres salient was changed to a maximum effort after a weather delay on 11 July, due to the extent of the opposition of the German Luftstreitkräfte. The Germans had been sending larger formations into action and 12 July had the greatest amount of air activity since the war had begun. Thirty German fighters engaged British and French fighters of the Service Aéronautique in a dogfight lasting an hour, the Royal Flying Corps losing nine aircraft and the Luftstreitkräfte fourteen. The Germans resisted the British and French air effort until the end of July, when their losses forced a change to more defensive tactics. The attack was delayed on 1 July at the request of General François Anthoine, commander of the French First Army as the French needed more time to prepare artillery emplacements. On 7 July, Gough asked for a delay of five days. Some British heavy artillery had been lost to the German counter-bombardment, some delayed in arriving and bad weather had hampered the programme of counter-battery fire. Haig agreed to delay until the 28 July. Anthoine then requested another delay because the poor weather had slowed his artillery preparation and after Gough supported Anthoine, Haig reluctantly agreed to delay to 31 July, even though this meant postponing Operation Hush from 7–8 August to the next period of high tides.

Plan of attack
The first of a series of set-piece attacks was to begin with an advance to three objectives, the blue, black and green lines, through the German front line system and then the Albrecht (second) and Wilhelm (third) lines, which were approximately from the British front line, at any of which a halt could be called if necessary. Local advances to the red line (fourth objective) 1000 – further forward, by patrols from the reserve brigades into undefended ground, were left to the discretion of divisional commanders. The British Fifth Army had 752 heavy guns and 1,442 field guns, with support from 300 heavy guns and 240 field guns belonging to the French First Army in the north and 112 heavy guns and 210 field guns of British Second Army to the south. Gough also intended to use 120 tanks to support the attack, with another 48 held in reserve. Gough had five divisions of cavalry, one brigade of which was to be deployed, if XIV Corps reached its objectives. The preliminary bombardment was intended to destroy German strong-points and trenches, cut barbed wire entanglements around German positions and to suppress German artillery with counter-battery fire. The first wave of infantry would advance under a creeping barrage advancing 100 yd every four minutes, followed by more infantry advancing in columns or in artillery formation. British intelligence expected the Germans to make the Albrecht (second) line their main line of resistance and to hold back counter-attacks until the British advance reached it, except on the Gheluvelt plateau, where British intelligence expected the Germans to counter-attack quickly, given the importance of this commanding ground to both sides. II Corps faced the Gheluvelt plateau and was given closer objectives than the other British Fifth Army corps, 1000 yd forward at Klein Zillebeke in the south and 2500 yd at the junction with XIX Corps, on the Ypres–Roulers railway to the north. II Corps had five divisions at its disposal, compared to four each in the XIX, XVIII and XIV Corps. Three divisions and a brigade from one of the two divisions in reserve, would attack with support from approximately 43% of the Fifth Army's artillery and artillery of X Corps on the left flank of Second Army.

German defensive preparations
The German Fourth Army operation order for the defensive battle was issued on 27 June. German defences had been arranged as a "forward zone", "main battle zone" and "rearward battle zone". The defence in depth began with a front system of three breastworks each about 200 yd apart, garrisoned by the four companies of each front battalion, with listening-posts in no man's land. About 2000 yd behind these works was the Albrecht (second) line, a secondary or "artillery protective line" that marked the rear boundary of the "forward zone". Companies of the support battalions were located at the back of the "forward zone" with half in the pillboxes of the Albrecht (second) line. Dispersed in front of the Albrecht (second) line were divisional sharpshooter machine-gun nests.

The Albrecht (second) line marked the front of the main zone with the Wilhelm (third) line, located a further 2000 yd away, marking the rear of the main zone. This zone contained most of the field artillery supporting the front divisions. In pillboxes of the Wilhelm (third) line were reserve battalions of the front-line regiments in divisional reserve. The rearward zone, located between the Wilhem (third) line and Flandern I, contained the support and reserve assembly areas for the Eingreif divisions. The German failures at the Battle of Verdun in December 1916 and at the Battle of Arras in April 1917 had given more importance to these areas, since the forward zones had been overrun and the garrisons lost. It was anticipated that the main defensive engagement would take place in the "main battle zone", against attackers who had been slowed and depleted by the forward garrisons, reinforced if need be by the Eingreif divisions.

The Germans planned a rigid defence of the front system and forward zone supported by counter-attacks. Local withdrawals according to the concept of elastic defence, was rejected by Von Lossberg the new Fourth Army Chief of Staff, who believed that they would disorganise troops moving forward to counter-attack. Front line troops were not expected to cling to shelters, which were man traps but evacuate them as soon as the battle began and move forward and to the flanks to avoid British fire and to counter-attack. A small number of machine-gun nests and permanent garrisons were separate from the counter-attack organisation, to provide a framework for the re-establishment of defence in depth once an attack had been repulsed. German infantry equipment had recently been improved by the arrival of thirty-six MG08/15 machine-guns per regiment, which gave German units more means for fire and manoeuvre.

Second Army
Due to the excellent observation possessed by the Germans, zero hour had been chosen for dawn at 3:50 a.m. but with mist and clouds at 500 –, it was still dark when the British bombardment began. The shelling was maintained for six minutes, while the British infantry crossed the 200 – of no man's land, then the barrage began to creep forward at a rate of 100 yd in four minutes. The attack extended from opposite Deulemont in the Second Army area, to the boundary with the Fifth Army, with the intention of convincing the Germans that a serious effort was being made to capture the Warneton–Zandvoorde line. The II Anzac Corps took the German outpost line west of the Lys river. The New Zealand Division captured La Basse Ville, south-west of Warneton, in street fighting with the German garrison, who eventually withdrew towards Warneton and the 3rd Australian Division captured outposts and strongpoints of the Warneton line near Gapaard.

To the north, IX Corps with the 39th and 19th divisions advanced 500 yd astride the Wambeke and Roosebeke streams and down the Oosttaverne spur between them to the blue line (first objective) 1000 – forward. The 19th Division attacked from Bee Farm in the south to Forret in the north. Two battalions of the 37th Division were attached to the right flank of the 19th Division to capture the blue line, from July to Bee Farms and revert to the command of the 37th Division for the next phase, for an attack south of July Farm. The 19th Division attack was conducted by the 56th Brigade with three attacking battalions and one in reserve. Each battalion assembled in the front line and the support battalions took post in the old British front line made redundant by the Battle of Messines Ridge in June and advanced to occupy the vacated front-line positions when the attack began. Artillery support came from the 19th divisional artillery, the left group of the 37th divisional artillery and two 6-inch batteries of the IX Corps heavy artillery; a machine-gun barrage was to be fired by about 30 machine-guns. The right battalion reached the objective very quickly, capturing Junction Buildings, Tiny and Spider farms as the 63rd Brigade battalions of the 37th Division formed a defensive flank by 4:10 a.m. One of the 37th Division battalions had gained touch with the rest of their division on the right but a gap of 300 yd had opened between Wasp Farm and Fly Buildings. Further to the left a 19th Division battalion had reached the blue line but further on the left, companies of the next attacking battalion has been pushed back south and south-west of Forret Farm. Prisoners claimed that the attack was expected later in the day and that a measure of surprise was obtained. Mopping up and consolidation began although the unexpected darkness made this difficult.

At about 5:30 a.m. German artillery fire increased and German soldiers were seen dribbling forward near Pillegrem's Farm, east of the junction with the 37th Division. Engineers and pioneers had begun work on strongpoints and communication trenches, despite the interference of the German barrage and by 11:00 a.m. had turned Tiny Farm into a strongpoint and completed communication trenches back to the old front line. More Germans were seen dribbling forward and small-arms fire became intense, when at 6:40 a.m. a smoke screen rose at the junction of the 19th and 37th divisions, the Germans attacked at 7:40 a.m. and overran some of the 63rd Brigade troops on the far right, only a small number getting back to Tiny Farm. Reinforcements from the 19th Division were prevented from reaching the old front line by German machine-gun fire. More reinforcements arrived and defensive flanks were formed, until a counter-attack on Rifle Farm was organised at 8:00 p.m., which succeeded until a fresh German attack moments later forced it back again. A second attack in the north on Forret Farm was repulsed late in the day and the division was ordered to consolidate.

X Corps attacked with the 41st Division, on either side of the Comines canal, captured Hollebeke village and dug in 500 – east of Battle Wood. Much of the X Corps artillery was used to help the Fifth Army by counter-battery fire on the German artillery concentration behind Zandvoorde. The 41st Division attack was hampered by frequent German artillery bombardments in the days before the attack and the officers laying out markings for the assembly tapes during the night of 30 July, exchanged fire with a German patrol. High explosive and gas shelling never stopped and one battalion lost 100 casualties in the last few days before the attack. At zero hour the attack began and the division advanced down the hill to the first German outposts. At one part of the battlefield German pillboxes had been built in lines from the front-line to the rear, from which machine-gunners kept up a steady fire. The strongpoints on the left were quickly suppressed but those on the right held out for longer and caused many casualties, before German infantry sallied from shelters, between the front and support lines on the right, before being repulsed by British small arms fire and that of a Vickers machine-gun fired by the Colonel in command of the battalion. Mopping-up the remaining pillboxes failed due to the number of casualties and a shortage of ammunition. It began to and at 4:00 a.m. many Germans were seen massing for a counter-attack. Reinforcements were called for and rapid fire opened on the German infantry but the attack succeeded in reaching the pillboxes still holding out on the right. The British artillery began firing as reinforcements arrived, the Germans were forced back and the last pillboxes captured. The front line had been advanced about 600 – on a front of 2500 yd, from south of Hollebeke north to the area east of Klein Zillebeke.

Fifth Army
The attack began at 3:50 a.m., which was intended to coincide with dawn but low cloud meant that it was still dark. The main British effort in the offensive was made by II Corps across the Ghelveult Plateau, on the southern flank of the Fifth Army. II Corps had the most difficult task, advancing against the principal German defensive concentration of artillery, ground-holding and Eingreif divisions. The 17th Brigade on the right of 24th Division reached its objective 1000 yd east of Klein Zillebeke. The 73rd Brigade in the centre was stopped by German pillboxes at Lower Star Post and 72nd Brigade on the left reached the Bassevillebeek but then had to withdraw to a line south from Bodmin Copse, a few hundred yards short of the blue line (first objective).

The 30th Division with a brigade of the 18th Division, had to advance across the Gheluvelt plateau to Glencorse Wood. The 21st Brigade on the right lost the barrage, as it crossed the wreckage of Sanctuary Wood and took until 6:00 a.m. to capture Stirling Castle Ridge. Attempts to advance further were stopped by German machine-gun fire. The 90th Brigade to the left was stopped on the first objective. German artillery fire fell on Sanctuary Wood and Chateau Wood from 5:00 a.m. and succeeded in stopping the advance, except for a short move forward of about 300 yd south of Westhoek. In the dark a battalion had veered left into Chateau Wood, in the 8th Division sector and reported that it had captured Glencorse Wood. The attached 53rd Brigade of 18th Division moved forward, into ground that both divisions believed to be clear of German defenders, it was not until 9:00 a.m. that the mistake became known to the divisional commanders. The 53rd Brigade spent the rest of the day attacking an area that 30th Division had been intended to clear. 30th Division and 24th Division failed to advance far due to the boggy ground, loss of direction in the dark and because much of the German machine-gun defence on this section of the front remained intact.

The 8th Division advanced towards Westhoek and took the Blue and Black lines relatively easily. The southern flank then became exposed to the concentrated fire of German machine-guns from Nonne Boschen and Glencorse Wood in the area to be taken by the 30th Division. The difficulties of the 30th Division further south were unknown to the 8th Division, until just before the 25th Brigade was due to advance over Westhoek Ridge. Brigadier-General Coffin decided that it was too late to stop the attack and sent a company of the reserve battalion to fill the gap to the south, which was not enough to stop German enfilade fire, so the Brigade consolidated on the reverse slope and held the crest with Lewis-gun posts. Pockets of ground lost to German counter-attacks were regained by British counter-attacks. British artillery barrages made it impossible for German infantry advance further in this area.

XIX Corps attacked with 15th Division on the right, next to the II Corps boundary along the Ypres–Roulers railway and 55th Division north to just short of St Julien. Their objective was the black line up the bare slope of Frezenberg Ridge, then across the valley of the Steenbeek to the green line on the far side. If German resistance collapsed, reserve brigades were to advance to the red line beyond Gravenstafel. The advance went well but then increasing resistance from fortified farms caused delays. Several tanks managed to follow the British infantry and attack strong-points like Bank Farm and Border House, allowing the advance to continue. After a pause for consolidation on the black line, the reserve brigades of the XIX Corps divisions began their advance to the green line a mile beyond, as the sun came out and a mist formed. On the right the advance encountered enfilade fire, from the area not occupied by 8th Division beyond the Ypres–Roulers railway. 164th Brigade of 55th Division had a hard fight through many German strong-points but took Hill 35 and crossed the Wilhelm (second) line, an eventual advance of about 4000 yd. Patrols pressed beyond the Zonnebeek–Langemarck road, one platoon taking fifty prisoners at Aviatik Farm on Gravenstafel spur.

XVIII Corps reached the first objective and after an hour moved down to the Steenbeek, one of the muddiest parts of the battlefield, behind a smoke and shrapnel barrage. The 39th and 51st Divisions then established themselves on the stream for 3000 yd, from St Julien to the Pilckem–Langemarck road. Several tanks were able to help capture strong-points delaying the advance and outposts were established across the stream.

The attack had most success in the north in the area of XIV Corps, with the Guards Division and 38th Division and I Corps of the French First Army. A lack of German activity east of the Yser canal had led to the Guards Division crossing it without artillery preparation in the afternoon of 27 July. The German front line was found to be empty so the Guards lurked forward 500 – beyond the canal, as did the French 1st Division on the left. The 38th Division front line was on the east side and it moved forward slightly against German small-arms and artillery-fire. On this section of the front, the Entente forces advanced 3000 – to the line of the Steenbeek river. The preliminary bombardment had succeeded in destroying the front line of the German position and the creeping barrage supported the infantry attack at least as far as the first objective. The infantry and some tanks dealt with German strongpoints encountered after the first line and forward battle zone had been penetrated, pushing on towards the further objectives. A number of field batteries moved forward once the black line had been captured, to join those established there before the attack, which had remained silent to avoid detection. Small cavalry probes were also carried out but German fire stopped them before they reached the green line.

Ire Armée
The French attacked with two divisions of the First Corps on a front of 3000 yd, from the left of the Guards Division to Steenstraat. After a delay until 2:30 p.m. on the right at Colonel's Wood, caused by fire from German pillboxes, the French completed their advance to the final objective and then went further to capture Bixschoote.

Air operations
On 26 July 37 British fighters engaged fifty Albatros scouts near Polygon Wood. During the melée four German reconnaissance aircraft were able to slip over the line and reconnoitre. Next evening eight British aircraft over Menin lured about twenty Albatros scouts to Polygon Wood, where 59 British fighters were waiting. Allied and German aircraft in the vicinity joined in the dogfight and after an hour the surviving German aircraft withdrew. The British decoys shot down six German aircraft and the ambushers another three while the British lost two aircraft. On 27 July a British reconnaissance aircraft detected an apparent German tactical withdrawal, which enabled XIV Corps to occupy 3000 yd of the German front line. Next day the fine weather allowed the British to conduct a large amount of air observation for counter-battery fire and to detect numerous German batteries which had been moved.

By 31 July, the Allied air concentration from the Lys River to the sea consisted of 840 aircraft, 330 being fighter aircraft and the German Fourth Army had about 600 aircraft, 200 being single-seat fighters. Operations to deprive the Germans of air observation over the attack front were curtailed by poor weather on 29 and 30 July. On 31 July, low cloud returned and stopped the air operation in support of the ground offensive. Small numbers of aircraft were sent out to seek targets of opportunity and a small amount of contact patrolling was managed at very low level, giving some information about the progress of the ground battle and leaving thirty British aircraft damaged by bullets and shells.

German Fourth Army counter-attacks
At noon the advance on the II Corps front had been stopped by the local German defenders and their artillery. The arrival of the British advance further north on the green line, 500 yd beyond the Steenbeek on the XIX Corps front at about 11:00 a.m. took a long time to be communicated to the British divisional headquarters because of mist, slow going by runners, cut signal cables and poor reconnaissance results from contact-patrol aircraft, caused by troops being unwilling to light flares while overlooked by German defences. Around 3:00 p.m. Gough ordered all XIX Corps troops to advance to the green line, in support of the three brigades which had reached it. Delays persisted and a German force approaching from behind the Broodseinde–Passchendaele ridge was not seen by British aircraft. A message from a ground observer did not reach 15th Division headquarters until 12:53 p.m. and rain began soon after, cutting off the view of advanced British troops by artillery observers.

A German creeping barrage began at 2:00 p.m. along XIX Corps front, then German troops attacked the flanks of the most advanced British positions. The 39th Division was pushed back to St Julien, exposing the left of the 55th Division, just as it was attacked frontally over the Zonnebeke spur by six waves of German infantry, preceded by a barrage and three aircraft which bombed and machine-gunned British troops. Attempts to hold the ground between the black and green lines failed, due to the communication breakdown, the speed of the German advance and worsening visibility as the rain increased during the afternoon. The 55th and 15th division brigades beyond the black line, were rolled up from north to south and either retreated or were overrun. It took until 6:00 p.m. for the Germans to reach the Steenbeek, as the downpour added to the mud and flooding in the valley. When the Germans were 300 yd from the black line, the British stopped the German advance with artillery and machine-gun fire.

The success of the British advance in the centre of the front caused serious concern to the Germans. The defensive system was designed to deal with some penetration but it was meant to prevent the 4000 yd advance that XVIII and XIX Corps had achieved. German reserves from the vicinity of Passchendaele, had been able to begin their counter-attack at 11:00–11:30 a.m. when the three British brigades facing the counter-attack by regiments of the German 221st and 50th Reserve Divisions of Group Ypres, were depleted and thinly spread. The British brigades could not communicate with their artillery due to the rain and because the Germans also used smoke shell in their creeping barrage. The German counter-attack was able to drive the British back from the green line along the Zonnebek–Langemarck road, pushing XIX Corps back to the black line. The Germans also recaptured St Julien just west of the green line on the XVIII Corps front, where the counter-attack was stopped by mud, artillery and machine-gun fire. The three most advanced British brigades had lost 70% casualties by the time they had withdrawn from the green line.

On the flanks of the Entente attack, German counter-attacks had little success. In the XIV Corps area, German attacks made no impression against British troops, who had had time to dig in but managed to push back a small bridgehead of the 38th Division from the east bank of the Steenbeek, after having suffered heavy losses from British artillery, when advancing around Langemarck. The Guards Division north of the Ypres–Staden railway held its ground; the French repulsed the Germans around St Janshoek and followed up to capture Bixschoote. German counter-attacks in the afternoon against II Corps on the Gheluvelt plateau, intended to recapture Westhoek Ridge, were able to advance a short distance from Glencorse Wood, before the 18th Division artillery and a counter-attack pushed them back again. In the Second Army area south of the plateau at La Basse Ville, a powerful attack at 3:30 p.m. was repulsed by the New Zealand Division. X Corps also managed to hold its gains around Klein Zillibeke against a big German attack at 7:00 p.m.

Casualties
The British Official History gave Fifth Army casualties for 31 July – 3 August as 27,001; 3,697 being killed. Second Army casualties 31 July – 2 August were 4,819; 769 killed, the 19th Division losing 870 casualties. German Fourth Army casualties for 21–31 July were approximately 30,000, excluding wounded whose recovery was to be expected in a reasonable time, for which J. E. Edmonds the British Official Historian, added another 10,000, a practice which has been questioned ever since. According to Albrecht von Thaer, a staff officer at Group Wytschaete, units may have survived physically but they no longer had the mental ability to continue.

Subsequent operations
German artillery kept up a heavy fire on the new British front line and along with the rain caused great difficulty in consolidating the captured ground. In the Second Army area, on 1 August, a German counter-attack on the front of the 3rd Australian Division, reached the Warneton Line before being stopped by artillery and machine-gun fire. A planned attack by the 19th and 39th divisions on 3 August, to regain the portion of the first objective (blue line) was cancelled when a battalion moved forward and occupied the ground unopposed. The 41st Division captured Forret Farm on the night of 1/2 August and the 19th Division pushed observation posts forward to the blue line. A German Stormtroop (Stoßtrupp) attack at 5:00 a.m. on 5 August, on the front of the 41st Division (X Corps) captured Hollebeke village and established posts near Forret Farm, under cover of a heavy and accurate artillery bombardment in thick mist. The British SOS flares were too wet to light, the barrage cut the telephone lines and visual signalling failed.

About 100 Stormtroops rushed Forret Farm and a nearby trench. Three posts were organised by the neighbouring 19th Division battalion, which counter-attacked the Germans from three directions, despite the Germans getting a machine-gun into action. As the British approached the farm, about fifty of the Germans tried to surrender but then lay down and resumed firing. The Germans retreated as the farm was rushed and some prisoners were taken, patrols then followed the German troops and took more prisoners. The position was handed over to the 41st Division by 11:00 a.m.; at about 9:00 a.m. the mist had suddenly lifted and revealed a force of about 200 German Stoßtruppen near "The Twins", which was engaged with small-arms fire and then scattered by artillery-fire. More German attacks on 6 August failed to reach the village.

On the Fifth Army front, a German counter-attack on the boundary of II and XIX Corps, managed to push back the 8th Division for a short distance south of the Ypres–Roulers railway. North of the railway the 15th Division stopped the attack with artillery fire. Two battalions of the 8th Division counter-attacked and restored the original front line by 9:00 p.m.. The Germans renewed the attack on the 15th and 55th Divisions in the afternoon of 2 August, being repulsed from the area around Pommern Redoubt. A second attempt at 5:00 p.m. was "crushed" by artillery fire, the Germans retiring behind Hill 35. German troops reported in Kitchener's Wood opposite the 39th Division were heavily bombarded, St Julien was occupied and posts established across the Steenbeek north of the village; more advanced posts were established by the 51st Division on 3 August.

A German attack on 5 August recaptured part of Jehovah Trench from the 24th Division in the II Corps area, before being pushed out again next day. On 7 August the Germans managed to blow up a bridge over the Steenbeek at Chien Farm in the 20th Division area. On the night of 9 August the 11th Division (XVIII Corps) took the Maison Bulgare and Maison du Rasta pillboxes unopposed and pushed posts on the far side of the Steenbeek another 150 yd forward. An attempt by the 11th Division (XVIII Corps) to push forward was stopped by fire from Knoll 12 and the 29th Division (XIV Corps) took Passerelle Farm and established posts east of the Steenbeek, building twelve bridges across the river. The 20th Division (XIV Corps) inched forward on 13 August and attacked again on 14 August across the Steenbeek. Mill Mound and four "Mebu" (Mannschafts–Eisenbeton–Unterstände) shelters were captured but the attacking troops had to dig in short of the Au Bon Gite blockhouse, repulsing a German counter-attack next day.

Capture of Westhoek
The preliminary operation intended for 2 August was delayed by rain until 10 August and the general offensive was postponed to 16 August. II Corps attacked on the 10 August to take the part of the black line retained by the Germans on 31 July. British artillery fire was distributed across the battlefront for the general attack due later by the Fifth Army and First French armies, to the green line just east of the German Wilhelm (third) line, between Polygon Wood and Langemarck and for the crossing of the Steenbeek further north. German artillery fire was concentrated on the II and XIX Corps fronts. British counter-battery efforts were hampered by the adverse weather, which made air observation extremely difficult. Much of the counter-battery effort was wasted by the British, who were unable to see German artillery shift position and often bombarded empty emplacements. The state of the ground, German artillery fire and British artillery losses foreshadowed the situation in late October opposite Passchendaele ridge.

The 8th and 30th Divisions had been relieved by 25th and 18th Divisions by 4 August but postponements caused by the rain, meant that reliefs of the front-line troops every 48 hours had exhausted all of the battalions by the 10 August. On 10 August an attack by the 24th Division on Lower Star Post failed, after German sentries caught sight of the British troops assembling in moonlight. The principal advance was made by the 18th Division in the centre and succeeded quickly but German artillery began a SOS barrage at 6.00 a.m., from Stirling Castle to Westhoek, isolating the foremost infantry beyond Inverness Copse and in Glencorse Wood, as local German reserves began immediate counter-attacks. Around 7:00 p.m. German infantry advanced behind a smokescreen, recaptured the Copse and all but the north-west corner of Glencorse Wood. The 74th Brigade of the 25th Division advanced at 4:25 a.m., fast enough to evade the German barrage on the British front line and reached its objectives by 5:30 a.m., assisted by the firepower of five Royal Field Artillery brigades.

The German garrison of Westhoek was rushed, while on the right flank sniping and attacks by German aircraft, caused considerable casualties during the day. The division held its gains around Westhoek but lost 158 killed, 1,033 wounded and more than 100 missing. The difficulties encountered by the 18th Division in Glencorse Wood on the right, as it was pushed back towards its start line, allowed German snipers and machine-gun fire to obstruct consolidation in the 25th Division area, particularly on the right flank, as the German troops reoccupied positions lost earlier in the day. During the day and night of 10/11 August, the Germans made several attempts to counter-attack the 25th Division. Excellent liaison by SOS signal, daylight lamps, pigeons and runners, made British artillery-fire highly accurate on the German counter-attack troops in their assembly positions, preventing counter-attacks except for one at 7:15 p.m., which was repulsed by rifle and machine-gun fire. The 25th Division gains on Westhoek Ridge were held and by 14 August the arracking troops had been relieved by the 56th and 8th Divisions. Next day a small German attack at 4:30 a.m. retook a pillbox from the 8th Division, which was recaptured shortly after.

Air support
Major-General Hugh Trenchard, commander of the Royal Flying Corps, wrote to the ground commanders after the battle that a study of low-flying attacks on German troops had concluded that the effect was short-lived, though highly demoralising for the victims and equally stimulating to friendly infantry in the vicinity. Trenchard wrote that such attacks would have best effect when co-ordinated with ground operations. Trenchard emphasised that the infantry should be told that much of the air effort took place out of sight and than absence should not be taken for inactivity. Rain continued until 5 August and seriously interrupted artillery observation flying.