Editing Battle of Passchendaele (section)

==Battles==

===July{{ndash}}August===

{{main|Western Front tactics, 1917#The British set-piece attack, mid-1917|l1=The British set-piece attack, mid-1917}}

[[File:18pdrBoesinghe31July1917.jpg|thumb|{{centre|British [[Ordnance QF 18 pounder|18-pounder]] battery taking up new positions near Boesinghe, 31 July}}]]
Haig selected Gough to command the offensive on 30 April and on 10 June Gough and the Fifth Army headquarters took over the Ypres salient north of Messines Ridge. Gough planned an offensive based on the ''GHQ 1917'' plan and the instructions he had received from Haig.{{sfn|Edmonds|1991|p=127}} Gough held meetings with his corps commanders on 6 and 16 June, where the third objective, which included the {{lang|de|Wilhelmstellung}} (third line), a second-day objective in earlier plans, was added to the two objectives due to be taken on the first day. A fourth objective, the red line, was also given for the first day, to be attempted by fresh troops, at the discretion of divisional and corps commanders, in places where the German defence had collapsed.{{sfn|Edmonds|1991|pp=126–127, 431–432}} The attack was not planned as a breakthrough operation and {{lang|de|Flandern I Stellung}}, the fourth German defensive position, lay {{cvt|10000|–|12000|yd|mi+km}} behind the front line and was not an objective on the first day.{{sfn|Prior|Wilson|1996|pp=72–75}}

The Fifth Army plan was more ambitious than the plans devised by Rawlinson and Plumer, which had involved an advance of {{cvt|1000|–|1750|yd}} on the first day, by compressing their first three attacks into one day instead of three.{{sfn|Prior|Wilson|1996|pp=72–75}} Major-General [[John Humphrey Davidson|John Davidson]], Director of Operations at GHQ, wrote in a memorandum that there was "ambiguity as to what was meant by a step-by-step attack with limited objectives" and suggested reverting to a {{cvt|1750|yd}} advance on the first day to increase the concentration of British artillery.{{sfn|Davidson|2010|p=29}} Gough stressed the need to plan to exploit opportunities to take ground left temporarily undefended, more likely in the first attack, which would have the benefit of long preparation. This had not been done in earlier battles and vacant ground, there for the taking, had been re-occupied by the Germans. At the end of June, Haig added a division to II Corps (Lieutenant-General [[Claud Jacob]]) from the Second Army and next day, after meeting with Gough and General [[Herbert Plumer, 1st Viscount Plumer|Herbert Plumer]], the [[Second Army (United Kingdom)|Second Army]] commander, Haig endorsed the Fifth Army plan.{{sfn|Edmonds|1991|p=440}}

====Battle of Pilckem Ridge====

{{main|Battle of Pilckem Ridge}}

[[File:The Battle of Passchendaele, July-november 1917 Q5726.jpg|thumb|{{centre|German prisoners and British wounded cross the Yser Canal near Boesinghe, 31 July 1917. ([[Imperial War Museum|IWM]] Q5726)}}]]
The British attack began at {{nowrap|3:50&nbsp;a.m.}} on 31 July; the attack was to commence at dawn but a layer of unbroken low cloud meant that it was still dark when the infantry advanced.{{sfn|Prior|Wilson|1996|p=89}} The main attack, by [[II Corps (United Kingdom)|II Corps]] across the Ghelveult Plateau to the south, confronted the principal German defensive concentration of artillery, ground-holding divisions ({{lang|de|Stellungsdivisionen}}) and {{lang|de|Eingreif}} divisions. The attack had most success on the northern flank, on the fronts of [[XIV Corps (United Kingdom)|XIV Corps]] and the French First Army, both of which advanced {{cvt|2500|–|3000|yd|mi+km}} to the line of the Steenbeek river. In the centre, [[XVIII Corps (United Kingdom)|XVIII Corps]] and [[XIX Corps (United Kingdom)|XIX Corps]] pushed forward to the line of the Steenbeek (black line) to consolidate and sent fresh troops towards the green line and on the XIX Corps front to the red line, for an advance of about {{cvt|4000|yd}}. Group Ypres counter-attacked the flanks of the British break-in, supported by every artillery piece and aircraft within range, around noon. The Germans were able to drive the three British brigades back to the black line with {{nowrap|70 per cent}} casualties; the German advance was stopped at the black line by mud, artillery and machine-gun fire.{{sfn|Prior|Wilson|1996|pp=90–95}}

====Capture of Westhoek====

{{main|Capture of Westhoek}}

[[File:German defensive system, Flanders, mid-1917.jpg|thumb|{{centre|German defensive system, Flanders, mid-1917}}]]
After rain delays from 2 August, II Corps attacked again on 10 August, to capture the rest of the black line (second objective) on the Gheluvelt plateau. The infantry advance succeeded but German artillery-fire and infantry counter-attacks isolated the infantry of the 18th (Eastern) Division in Glencorse Wood. At about {{nowrap|7:00&nbsp;p.m.,}} German infantry attacked behind a smokescreen and recaptured all but the north-west corner of the wood; only the 25th Division gains on Westhoek Ridge to the north were held.{{sfn|Edmonds|1991|pp=185–187}} Lieutenant-Colonel [[Albrecht von Thaer]], Chief of Staff of {{lang|de|Gruppe Wijtschate}} (Group Wytschaete, the headquarters of the [[IX Reserve Corps (German Empire)|IX Reserve Corps]]), noted that casualties after {{nowrap|14 days}} in the line averaged {{nowrap|1,500–2,000 men,}} compared to {{nowrap|4,000 men}} on the Somme in 1916 and that German troop morale was higher than the year before.{{sfn|Liddle|1997|pp=45–58}}

====Battle of Hill 70====

{{Main|Capture of Oppy Wood|Battle of Hill 70}}

Attacks to threaten Lens and Lille were to be made by the [[First Army (United Kingdom)|First Army]] in late June near Gavrelle and Oppy, along the Souchez river. The objective was to eliminate a German salient between Avion and the west end of [[Lens, Pas-de-Calais|Lens]], by taking reservoir Hill (Hill 65) and Hill 70. The attacks were conducted earlier than planned to use heavy and siege artillery before it was transferred to Ypres, the Souchez operation being cut back and the attack on Hill 70 postponed.{{sfn|Edmonds|1991|pp=112–113}} The Battle of Hill 70, {{cvt|30|mi}} south of Ypres, eventually took place from 15 to 25 August. The [[Canadian Corps]] fought four divisions of the German [[6th Army (German Empire)|6th Army]] in the operation. The capture of Hill 70 was a costly success in which three Canadian divisions inflicted many casualties on the German divisions opposite and pinned down troops reserved for the relief of tired divisions in Flanders.{{sfn|Edmonds|1991|pp=219–230}} [[Hermann von Kuhl]], chief of staff of Army Group Crown Prince Rupprecht, wrote later that it was a costly defeat and wrecked the plan for relieving fought-out (exhausted) divisions in Flanders.{{sfn|Terraine|1977|p=234}}

====Battle of Langemarck====

{{main|Battle of Langemarck (1917)|Operation Hush}}

The Battle of Langemarck was fought from {{nowrap|16 to 18 August;}} the Fifth Army headquarters was influenced by the effect that delay would have on Operation Hush, which needed the high tides due at the end of August or it would have to be postponed for a month. Gough intended that the rest of the green line, just beyond the {{lang|de|Wilhelmstellung}} (German third line), from Polygon Wood to Langemarck, was to be captured and the Steenbeek crossed further north.{{sfn|Edmonds|1991|pp=189–202}} In the II Corps area, the disappointment of 10 August was repeated, with the infantry managing to advance, then being isolated by German artillery and forced back to their start line by German counter-attacks, except in the 25th Division area near Westhoek. Attempts by the German infantry to advance further were stopped by British artillery-fire with many casualties.{{sfn|Edmonds|1991|p=194}} The advance further north in the XVIII Corps area retook and held the north end of St Julien and the area south-east of Langemarck, while XIV Corps captured Langemarck and the {{lang|de|Wilhelmstellung}} north of the Ypres–Staden railway, near the Kortebeek stream. The French First Army conformed, pushing up to the Kortebeek and St Jansbeck stream west of the northern stretch of the {{lang|de|Wilhelmstellung}}, where it crossed to the east side of the Kortebeek.{{sfn|Edmonds|1991|p=201}}

====Local attacks====

{{see also|Gheluvelt Plateau actions, July–August 1917|l1=Gheluvelt Plateau|Action of the Cockcroft|Action of 22 August 1917}}

[[File:AAGunMorbecque29August1917-2.jpeg|thumb|{{centre|British anti-aircraft gun at Morbecque, 29 August 1917}}]]
On the higher ground, the Germans continued to inflict many losses on the British divisions beyond Langemarck but on 19 August, after two fine dry days, XVIII Corps conducted a novel infantry, tank, aircraft and artillery operation. German strongpoints and pillboxes along the St Julien–Poelcappelle road in front of the {{lang|de|Wilhelmstellung}} were captured. On 22 August, more ground was gained by XIX and XVIII corps but the tactical disadvantage of being overlooked by the Germans continued.{{sfn|Edmonds|1991|p=203}} A II Corps attack on the Gheluvelt Plateau from 22 to 24 August, to capture Nonne Bosschen, Glencorse Wood and Inverness Copse, failed in fighting that was costly to both sides.{{sfn|Edmonds|1991|pp=202–205}} Gough laid down a new infantry formation of skirmish lines to be followed by "worms" on 24 August and Cavan noted that pillboxes should be attacked on a broad front, to engage them simultaneously.{{sfn|Simpson|2001|pp=130–134}} Another general offensive intended for 25 August, was delayed by the failure of the preliminary attacks and then postponed due to more bad weather.{{sfn|Rogers|2010|pp=162–167}} On 27 August, II Corps tried a combined tank and infantry attack but the tanks bogged, the attack failed and Haig called a halt to operations until the weather improved.{{sfn|Edmonds|1991|p=208}}

====Weather====
[[File:18pdrInMudZillebeke9August1917.jpg|thumb|left|{{centre|Royal Field Artillery gunners hauling an 18-pounder field gun out of the mud near Zillebeke, 9 August 1917}}]]
In ''Field Marshal Earl Haig'' (1929), Brigadier-General [[John Charteris]], the BEF Chief of Intelligence from 1915 to 1918, wrote that

{{blockquote|Careful investigation of records of more than eighty years showed that in Flanders the weather broke early each August with the regularity of the Indian monsoon: once the Autumn rains set in difficulties would be greatly enhanced....Unfortunately, there now set in the wettest August for thirty years.|Charteris{{sfn|Charteris|1929|pp=272–273}}}}

only the first part of which was quoted by Lloyd George (1934), Liddell Hart (1934) and Leon Wolff (1959); in a 1997 essay, John Hussey called the passage by Charteris "baffling".{{sfn|Hussey|1997|p=155}} The BEF had set up a Meteorological Section under [[Ernest Gold (meteorologist)|Ernest Gold]] in 1915, which by the end of 1917 had {{nowrap|16 officers}} and {{nowrap|82 men.}} The section predicted the warm weather and thunderstorms of 7 to 14 June; in a letter to the press of 17 January 1958, Gold wrote that the facts of the Flanders climate contradicted Charteris.{{sfn|Hussey|1997|p=153}} In 1989, Philip Griffiths examined August weather in Flanders for the thirty years before 1916 and found that,

{{blockquote|...there is no reason to suggest that the weather broke early in the month with any regularity.|Griffiths{{sfn|Hussey|1997|pp=147–148}}}}

From 1901 to 1916, records from a weather station at [[Cap Gris Nez]] showed that {{nowrap|65 per cent}} of August days were dry and that from 1913 to 1916, there were {{nowrap|26, 23, 23 and 21}} rainless days and monthly rainfall of {{cvt|17|,|28|,|22|and| 96|mm|in}};

{{blockquote|...during the summers preceding the Flanders campaign August days were more often dry than wet.|Griffiths{{sfn|Hussey|1997|p=148}}}}

There were {{cvt|127|mm}} of rain in August 1917 and {{cvt|84|mm}} of the total fell on {{nowrap|1, 8, 14, 26 and}} {{nowrap|27 August.}} The month was overcast and windless, which much reduced evaporation. Divided into two ten-day and an eleven-day period, there were {{cvt|53.6|,|32.4|and|41.3|mm}} of rain; in the {{nowrap|61 hours}} before {{nowrap|6:00&nbsp;p.m.}} on 31 July, {{cvt|12.5|mm}} fell. From {{nowrap|6:00&nbsp;p.m.}} on 31 July to {{nowrap|6:00&nbsp;p.m.}} on 4 August, there was another {{cvt|63|mm}} of rain. August 1917 had three dry days and {{nowrap|14 days}} with less than {{cvt|1|mm}} of rain. Three days were sunless and one had six minutes of sunshine; from 1 to 27 August there were {{nowrap|178.1 hours}} of sunshine, an average of {{nowrap|6.6 hours}} per day. Hussey wrote that the wet weather in August 1917 was exceptional and that Haig had been justified in expecting little rain and that it would be dried swiftly by sunshine and breezes.{{sfn|Hussey|1997|pp=149–151}}

====Verdun====

{{main|Battle of Verdun#20–26 August 1917|l1=Verdun, August 1917}}

Petain had committed the French Second Army to an attack at Verdun in mid-July, in support of the Flanders offensive. The attack was delayed, partly due to mutinies in the French army after the failure of the [[Nivelle Offensive]] and because of a German attack at Verdun from 28 to 29 June, which captured some of the French jumping-off points. A French counter-attack on 17 July re-captured the ground, the Germans regained it on 1 August, then took ground on the east bank on 16 August.{{sfn|Doughty|2005|pp=380–383}} The French attacked on 20 August and by 9 September had taken {{nowrap|10,000 prisoners.}} Sporadic fighting continued into October, adding to the German difficulties on the Western Front and elsewhere. Ludendorff wrote

{{blockquote|On the left bank, close to the Meuse, one division had failed&nbsp;... and yet both here and in Flanders everything possible had been done to avoid failure&nbsp;... The French army was once more capable of the offensive. It had quickly overcome its depression.|Ludendorff: ''Memoirs''{{sfn|Terraine|1977|p=235}}}}

No German counter-attack was possible because the local {{lang|de|Eingreif}} divisions had been transferred to Flanders.{{sfn|Edmonds|1991|p=230}}

===September–October===

{{main|Western Front tactics, 1917#The British set-piece attack, late 1917|l1 = The British set-piece attack, late 1917}}

[[File:The Battle of Passchendaele, July-november 1917 Q6416.jpg|thumb|{{centre|Derelict tank used as the roof of a dug out, Zillebeke, 20 September 1917 (Q6416)}}]]
The [[4th Army (German Empire)|4th Army]] had held on to the Gheluvelt Plateau in August but its casualties worsened the German manpower shortage.{{sfn|Sheldon|2007|pp=119–120}} Haig transferred the main offensive effort to the Second Army on 25 August and moved the northern boundary of the Second Army closer to the Ypres–Roulers railway. More heavy artillery was sent to Flanders from the armies further south and placed opposite the Gheluvelt Plateau.{{sfn|Nicholson|1964|p=308}} Plumer continued the tactical evolution of the Fifth Army during its slow and costly progress in August. After a pause of about three weeks, Plumer intended to capture the plateau in four steps, with six-day intervals to bring forward artillery and supplies.{{sfn|Edmonds|1991|p=237}} The Second Army attacks were to remain limited and infantry brigade tactics were changed to attack the first objective with a battalion each and the final one with two battalions, the opposite of the Fifth Army practice on 31 July, to adapt to the dispersed defences being encountered between the {{lang|de|Albrechtstellung}} and the {{lang|de|Wilhelmstellung}}.{{sfn|Marble|2003|loc=App 22}}

Plumer arranged for the medium and heavy artillery reinforcements reaching Flanders to be added to the creeping bombardment, which had been impossible with the amount of artillery available to the Fifth Army.{{sfn|Marble|2003|loc=App 22}} The tactical changes ensured that more infantry attacked on narrower fronts, to a shallower depth than on 31 July, like the Fifth Army attacks in August. The shorter and quicker advances possible once the ground dried were intended to be consolidated on tactically advantageous ground, especially on any reverse slopes in the area, with the infantry still in contact with the artillery and aircraft, ready to repulse counter-attacks.{{sfn|Nicholson|1964|p=308}} The faster tempo of operations was intended to add to German difficulties in replacing tired divisions through the railway bottlenecks behind the German front.{{sfn|Edmonds|1991|pp=236–242}} The pause in British attacks misled some of the German commanders and Albrecht von Thaer, the chief of staff of {{lang|de|Gruppe Wijtschate}}, wrote that it was "almost boring".{{sfn|Liddle|1997|pp=45–58}} Kuhl doubted that the offensive had ended but had changed his mind by 13 September; two divisions, thirteen heavy artillery batteries, twelve field batteries, three fighter squadrons and four other units of the {{lang|de|Luftstreitkräfte}} were transferred from the 4th Army.{{sfn|Terraine|1977|p=257}}

====German tactical changes====

{{main|Western Front tactics, 1917#German defensive changes, late 1917|l1=German defensive changes, late 1917}}

After setting objectives {{cvt|1|–|2|mi}} distant on 31 July, the British attempted shorter advances of approximately {{cvt|1500|yd}} in August but were unable to achieve these lesser objectives in the south of the battlefield, because the rain soaked ground and poor visibility were to the advantage of the defenders. After the dry spell in early September, British advances had been much quicker and the final objective was reached a few hours after dawn, which confounded the German counter-attack divisions. Having crossed {{cvt|2|mi}} of mud, the {{lang|de|Eingreif}} divisions found the British already dug in, with the German forward battle zone and its weak garrison gone beyond recapture.{{sfn|Wynne|1976|p=303}} In August, German front-line divisions had two regiments deployed in the front line, with the third regiment in reserve. The front battalions had needed to be relieved much more frequently than expected due to the power of British attacks, constant artillery-fire and the weather. Replacement units became mixed up with ones holding the front and reserve regiments had failed to intervene quickly, leaving front battalions unsupported until {{lang|de|Eingreif}} divisions arrived some hours later.{{sfn|Rogers|2010|p=168}}

In July and August, German counter-attack ({{lang|de|Eingreif}}) divisions had conducted an "advance to contact during mobile operations", which had given the Germans several costly defensive successes.{{sfn|Sheldon|2007|p=184}} After the [[Battle of the Menin Road Ridge]], German tactics were changed.{{sfn|Rogers|2010|p=168}} After another defeat on 26 September, the German commanders made more tactical changes to counter the more conservative form of limited attacks adopted by the British.{{sfn|Sheldon|2007|p=184}} German counter-attacks in September had been "assaults on reinforced field positions", due to the restrained nature of British infantry advances. The fine weather in early September had greatly eased British supply difficulties, especially in ammunition and the British made time to establish a defence in depth on captured ground, protected by standing artillery barrages. The British attacked in dry, clear conditions, with more aircraft over the battlefield for counter-attack reconnaissance. It had also been found in 1916 that corps headquarters had become aware of the situation from the reports of aircrew on contact-patrol, where reconnaissance aircraft flew low over the battlefield to map the positions of British troops.{{sfn|Jones|2002|p=173–175}} Brigade headquarters had been ignorant of events and arrangements were made for the swift transmission of information forwards. Systematic defensive artillery-fire was forfeited by the Germans, due to uncertainty over the position of their infantry, just when the British infantry benefited from the opposite. German counter-attacks were costly failures and on 28 September, Thaer wrote that the experience was "awful" and that he did not know what to do.{{sfnm|1a1=Edmonds|1y=1991|1pp=294–295|2a1=Liddle|2y=1997|2pp=45–58}}

Ludendorff ordered the {{lang|de|Stellungsdivisionen}} (ground holding divisions) to reinforce their front garrisons; all machine-guns, including those of the support and reserve battalions were sent into the forward zone, to form a cordon of four to eight guns every {{cvt|250|yd}}.{{sfn|Wynne|1976|pp=307–308}} The {{lang|de|Stellungsdivisionen}} were reinforced by the {{lang|de|Stoß}} (shock) regiments of {{lang|de|Eingreif}} divisions, which were moved into the artillery protective line behind the forward battle zone, to counter-attack sooner. The other regiments of the {{lang|de|Eingreif}} divisions were to be held back and used for a methodical counter-attack ({{lang|de|Gegenangriff}}) a day or two after and for spoiling attacks as the British reorganised.{{sfnm|1a1=Sheldon|1y=2007|1pp=190–191|2a1=Wynne|2y=1976|2p=307}}{{efn|The [[4th Guards Infantry Division (German Empire)|4th Guard Division]], [[4th Royal Bavarian Division|4th Bavarian Division]], [[6th Royal Bavarian Division|6th Bavarian Division]], [[10th Ersatz Division (German Empire)|10th Ersatz Division]], [[16th Division (German Empire)|16th Division]], [[19th Reserve Division (German Empire)|19th Reserve Division]], [[20th Division (German Empire)|20th Division]], 187th Division, 195th Division and [[45th Reserve Division (German Empire)|45th Reserve Division]] took part in the battle.{{sfn|USWD|1920}}}} More tactical changes were ordered on 30 September; operations to increase British infantry losses were to continue and gas bombardments were to be increased, weather permitting. Every effort was to be made to induce the British to reinforce their forward positions with infantry for the German artillery to bombard them.{{sfn|Sheldon|2007|pp=184–186}} Between 26 September and 3 October, the Germans attacked at least {{nowrap|24 times}} and Operation High Storm {{lang|de|Unternehmen Hohensturm}}, a {{lang|de|Gegenangriff}} (methodical counter-attack), to recapture the area around Zonnebeke was planned for 4 October.{{sfnm|1a1=Terraine|1y=1977|1p=278|2a1=Prior|2a2=Wilson|2y=1996|2p=135}}

====Battle of the Menin Road Ridge====

{{Main|Battle of the Menin Road Ridge}}

[[File:Battle of Menin Road - wounded at side of the road.jpg|thumb|{{centre|Wounded men at the side of a road after the Battle of Menin Road}}]]
The British plan for the battle fought from {{nowrap|20 to 25 September,}} included more emphasis on the use of heavy and medium artillery to destroy German concrete pill-boxes and machine-gun nests, which were more numerous in the battle zones being attacked, than behind the original July front line and to engage in more counter-battery fire. The British had {{nowrap|575 heavy}} and medium and {{nowrap|720 field}} guns and howitzers, more than double the quantity of artillery available at the Battle of Pilckem Ridge.{{sfn|Edmonds|1991|pp=238–239}} Aircraft were to be used for systematic air observation of German troop movements, to avoid the failures of previous battles, where too few aircrews had been burdened with too many duties and had flown in bad weather, which made their difficulties worse.{{sfn|Jones|2002|p=181}}

On 20 September, the Allies attacked on a {{cvt|14500|yd|mi+km}} front and by mid-morning had captured most of their objectives, to a depth of about {{cvt|1500|yd}}.{{sfn|Terraine|1977|p=261}} The Germans made many hasty counter-attacks ({{lang|de|Gegenstoße}}), beginning around {{nowrap|3:00&nbsp;p.m.}} until early evening, all of which failed to gain ground or made only a temporary penetration of the new British positions. The German defence had failed to stop a well-prepared attack made in good weather.{{sfn|Harris|2008|p=366}} Minor attacks took place after 20 September, as both sides jockeyed for position and reorganised their defences. A mutually-costly attack by the Germans on 25 September, recaptured pillboxes at the south western end of Polygon Wood. Next day, the German positions near the wood were swept away in the Battle of Polygon Wood.{{sfn|Sheldon|2007|p=165}}

====German counter-attack, 25 September====

{{main|Action of 25 September 1917}}

Two regiments of the German [[50th Reserve Division (German Empire)|50th Reserve Division]] attacked on a {{cvt|1800|yd}} front, either side of the Reutelbeek stream, supported by aircraft and {{nowrap|44 field}} and {{nowrap|20 heavy}} batteries of artillery, four times the usual amount for a division. The German infantry managed to advance on the flanks, about {{cvt|100|yd}} near the Menin road and {{cvt|600|yd}} north of the Reutelbeek. The infantry were supported by artillery-observation and ground-attack aircraft; a box-barrage was fired behind the British front-line, which isolated the British infantry from reinforcements and ammunition. Return-fire from the [[33rd Division (United Kingdom)|33rd Division]] and the [[15th Brigade (Australia)|15th Australian Brigade]] of the [[5th Division (Australia)|5th Australian Division]] along the southern edge of Polygon Wood to the north, forced the attackers under cover around some of the {{lang|de|Wilhelmstellung}} pillboxes, near Black Watch Corner, at the south-western edge of Polygon Wood. German attempts to reinforce the attacking troops failed, due to British artillery observers isolating the advanced German troops with artillery barrages.{{sfn|Edmonds|1991|pp=282–284}}

Plumer ordered the attack due on 26 September to go ahead but reduced the objectives of the 33rd Division. The 98th Brigade was to advance and cover the right flank of the 5th Australian Division and the 100th Brigade was to re-capture the lost ground further south. The 5th Australian Division advance the next day began with uncertainty as to the security of its right flank; the attack of the depleted 98th Brigade was delayed and only managed to reach Black Watch Corner, {{cvt|1000|yd}} short of its objectives. Reinforcements moved into the 5th Australian Division area and attacked south-westwards at noon as a silent (without artillery support) frontal attack was made from Black Watch Corner, because British troops were known to be holding out in the area. The attack succeeded by {{nowrap|2:00&nbsp;p.m.}} and later in the afternoon, the 100th Brigade re-took the ground lost north of the Menin road. Casualties in the 33rd Division were so great that it was relieved on 27 September by the 23rd Division, which had only been withdrawn on the night of {{nowrap|24/25 September.}}{{sfn|Edmonds|1991|pp=286–287}}

====Battle of Polygon Wood====

{{Main|Battle of Polygon Wood}}

[[File:Australian infantry small box respirators Ypres 1917.jpg|thumb|upright|{{centre|Australian infantry with [[small box respirator]] gas masks, Ypres, September 1917}}]]
The Second Army altered its Corps frontages soon after the attack of 20 September, for the next effort {{nowrap|(26 September – 3 October)}} so that each attacking division could be concentrated on a {{cvt|1000|yd}} front. Roads and light railways were extended to the new front line, to allow artillery and ammunition to be moved forward. The artillery of [[VIII Corps (United Kingdom)|VIII Corps]] and [[IX Corps (United Kingdom)|IX Corps]] on the southern flank, simulated preparations for attacks on Zandvoorde and Warneton. At {{nowrap|5.50&nbsp;a.m.}} on 26 September, five layers of barrage fired by British artillery and machine-guns began. Dust and smoke thickened the morning mist and the infantry advanced using compass bearings.{{sfn|Edmonds|1991|p=284}} Each of the three German ground-holding divisions attacked on 26 September had an {{lang|de|Eingreif}} division in support, twice the ratio of 20 September. No ground captured by the British was lost and German counter-attacks managed only to reach ground to which survivors of the front-line divisions had retired.{{sfn|Edmonds|1991|p=293}}

===October–November===

====German counter-attacks, 30 September – 4 October====

{{main|Actions of 30 September – 4 October 1917}}

At {{nowrap|4:00&nbsp;a.m.}} on 30 September, a thick mist covered the ground and at {{nowrap|4:30&nbsp;a.m.}} German artillery began a bombardment between the Menin road and the Reutelbeek. At {{nowrap|5:15&nbsp;a.m.,}} German troops emerged from the mist on an {{cvt|800|yd}} front.{{sfn|Sandilands|2003|pp=198–199}} The attack was supported by flame-throwers and German infantry throwing smoke- and hand-grenades. The British replied with small-arms fire and bombs, forcing the Germans to retreat in confusion but a post was lost south of the Menin road, then retaken by an immediate counter-attack. SOS rockets were not seen in the mist and the British artillery remained silent.{{sfn|Edmonds|1991|pp=301, 302}} The Germans were repulsed again at {{nowrap|6:00&nbsp;a.m.}} but German artillery-fire continued during the day.{{sfn|Sandilands|2003|pp=198–199}}

On 1 October, at {{nowrap|5:00&nbsp;a.m.,}} a German [[hurricane bombardment]] began from the Reutelbeek north to Polygon Wood and Black Watch Corner; by coincidence a Second Army practice barrage began at {{nowrap|5:15&nbsp;a.m.}} The British front line was cut off and German infantry attacked in three waves at {{nowrap|5:30&nbsp;a.m.}}{{sfn|Bean|1941|p=837}} Two determined German attacks were repulsed south of Cameron Covert, then at {{nowrap|7:00&nbsp;p.m.}} German troops massed near the Menin road. The German attack was defeated by small-arms fire and the British artillery, whose observers had seen the SOS rockets. The British were forced out of Cameron Covert and counter-attacked but a German attack began at the same time and the British were repulsed. Another German attack failed and the German troops dug in behind some old German barbed wire; after dark, more German attacks around Cameron Covert failed.{{sfn|Sandilands|2003|pp=200–204}} North of the covert near Polygon Wood, deep mud smothered German shells before they exploded but they still caused many casualties. Communication with the rear was lost and the Germans attacked all day but British SOS rockets remained visible and the attacks took no ground; after dark German attacks were repulsed by another three SOS barrages.{{sfn|Atkinson|2009|pp=410–412}}

{{lang|de|Unternehmen Hohensturm}} (Operation High Storm) was planned by {{lang|de|Gruppe Ypern}} to recapture the Tokio Spur from Zonnebeke south to Molenaarelsthoek at the eastern edge of Polygon Wood on 3 October.{{sfn|Bean|1941|p=846}} The attacking infantry from the 45th Reserve and the 4th Guard divisions were commanded by Major Freiherr von Schleinitz in the north and Lieutenant-Colonel Rave in the south.{{sfn|Bean|1941|p=847}} After the costly failure of the methodical counter-attack ( {{lang|de|Gegenangriff}}) on 1 October, the attack was put back to 4 October, rehearsals taking place from 2 to 3 October.{{sfn|Edmonds|1991|pp=303–304}} On the night of {{nowrap|3/4 October,}} the German commanders had doubts about the attack but decided to proceed with the {{lang|de|Gegenangriff}}, warning the artillery to be ready to commence defensive bombardments.{{sfn|Bean|1941|p=858}} A contact patrol aircraft was arranged to fly over the area at {{nowrap|7:30&nbsp;a.m.}}{{sfn|Bean|1941|p=847}}

====Battle of Broodseinde====

{{Main|Battle of Broodseinde}}

On 4 October, the British began the Battle of Broodseinde to complete the capture of the Gheluvelt Plateau and occupy Broodseinde Ridge. By coincidence, the Germans sought to recapture their defences around Zonnebeke with a {{lang|de|Gegenangriff}} at the same time.{{sfn|Prior|Wilson|1996|p=135}} The British attacked along a {{cvt|14000|yd|mi+km}} front and as the I Anzac Corps divisions began their advance towards Broodseinde Ridge, men were seen rising from shell-holes in no man's land and more German troops were found concealed in shell-craters. Most of the German troops of the [[45th Reserve Division (German Empire)|45th Reserve Division]] were overrun or retreated through the British barrage, then the Australians attacked pillboxes one-by-one and captured the village of Zonnebeke north of the ridge.{{sfnm|1a1=Bean|1y=1941|1pp=837, 847|2a1=Edmonds|2y=1991|2pp=304–307}} When the British barrage began on Broodseinde Ridge, the Keiberg Spur and Waterdamhoek, some of the German forward headquarters staffs only realised that they were under attack when British and Australian troops appeared.{{sfn|Bean|1941|pp=858–859}}

As news arrived of the great success of the attack, the head of GHQ Intelligence went to the Second Army headquarters to discuss exploitation. Plumer declined the suggestion, as eight fresh German divisions were behind the battlefield, with another six beyond them.{{sfn|Edmonds|1991|p=316}} Later in the day, Plumer had second thoughts and ordered I Anzac Corps to push on to the Keiberg spur, with support from the II Anzac Corps. The II Anzac Corps commander wanted to advance north-east towards Passchendaele village but the I Anzac Corps commander preferred to wait until artillery had been brought up and supply routes improved. The X Corps commander proposed an attack northward from In de Ster<!--place name--> into the southern flank of the Germans opposite I Anzac Corps. The 7th Division commander objected, due to uncertainty about the situation and the many casualties suffered by the 21st Division on the right flank and Plumer changed his mind again. During the morning, Gough had told the Fifth Army corps commanders to push on but when reports arrived of a repulse at 19 Metre Hill, the order was cancelled.{{sfn|Edmonds|1991|pp=315–317}}

====German defensive changes====

{{main|Western Front tactics, 1917#German defensive changes, late 1917|l1=German defensive changes, late 1917}}

[[File:NLS Haig - Troops moving up at eventide - men of a Yorkshire regiment on the march (cropped).jpg|thumb|{{centre|British soldiers moving forward during the Battle of Broodseinde. Photo by [[Ernest Brooks (photographer)|Ernest Brooks]].}}]]
On 7 October, the 4th Army again dispersed its troops in the front defence zone. Reserve battalions moved back behind the artillery protective line and the {{lang|de|Eingreif}} divisions were organised to intervene as swiftly as possible once an attack commenced, despite the risk of British artillery-fire. Counter-battery fire to suppress the British artillery was to be increased, to protect the {{lang|de|Eingreif}} divisions as they advanced.{{sfn|Wynne|1976|p=309}} All of the German divisions holding front zones were relieved and an extra division brought forward, because the British advances had lengthened the front line. Without the divisions necessary for a counter-offensive south of the Gheluvelt Plateau towards Kemmel Hill, Rupprecht began to plan for a slow withdrawal from the Ypres Salient, even at the risk of uncovering German positions further north and on the Belgian coast.{{sfn|Sheldon|2007|pp=228–229}}{{efn|195th, 16th, 4th Bavarian, 18th, 227th, 240th, 187th and 22nd Reserve divisions).{{sfn|USWD|1920}}}}

====Battle of Poelcappelle====

{{Main|Battle of Poelcappelle}}

The French First Army and British Second and Fifth armies attacked on 9 October, on a {{cvt|13500|yd|mi+km}} front, from south of Broodseinde to St Jansbeek, to advance half of the distance from Broodseinde ridge to Passchendaele, on the main front, which led to many casualties on both sides. Advances in the north of the attack front were retained by British and French troops but most of the ground taken in front of Passchendaele and on the Becelaere and Gheluvelt spurs was lost to German counter-attacks.{{sfn|Bean|1941|p=887}} General [[William Birdwood, 1st Baron Birdwood|William Birdwood]] later wrote that the return of heavy rain and mud sloughs was the main cause of the failure to hold captured ground. Kuhl concluded that the fighting strained German fighting power to the limit but that the German forces managed to prevent a breakthrough, although it was becoming much harder to replace losses.{{sfn|Terraine|1977|pp=287–288}}

====First Battle of Passchendaele====

{{Main|First Battle of Passchendaele}}

[[File:Passchendaele aerial view.jpg|thumb|{{centre|Aerial view of Passchendaele village before and after the battle}}]]
The First Battle of Passchendaele on 12 October 1917 was another Allied attempt to gain ground around Passchendaele. Heavy rain and mud again made movement difficult and little artillery could be brought closer to the front. Allied troops were exhausted and morale had fallen. After a modest British advance, German counter-attacks recovered most of the ground lost opposite Passchendaele, except for an area on the right of the Wallemolen spur. North of Poelcappelle, the XIV Corps of the Fifth Army advanced along the Broembeek some way up the Watervlietbeek and the Stadenrevebeek streams and the Guards Division captured the west end of the Vijwegen spur, gaining observation over the south end of Houthulst Forest.{{sfn|Edmonds|1991|pp=341–344}} There were {{nowrap|13,000 Allied}} casualties, including {{nowrap|2,735 New}} Zealanders, {{nowrap|845 of}} whom were dead or stranded in the mud of no-man's-land; it was one of the worst days in New Zealand military history.{{sfn|Liddle|1997|p=285}}<!--including {{nowrap|about 3,700 New}} Zealanders, {{nowrap|842 of}} whom were dead or stranded in the mud of no-man's-land;<ref>{{cite web|url=https://nzhistory.govt.nz/war/western-front-1917#heading5|title=1917: Arras, Messines and Passchendaele – 1917: Arras, Messines and Passchendaele – NZHistory, New Zealand history online|website=nzhistory.govt.nz|access-date=31 July 2017}}</ref>need printed sources for this if possible-->

At a conference on 13 October, Haig and the army commanders agreed that attacks would stop until the weather improved and roads could be extended, to carry more artillery and ammunition forward. The offensive was to continue, to reach a suitable line for the winter and to keep German attention on Flanders, with a French attack due on 23 October and the Third Army operation south of Arras scheduled for mid-November.{{sfn|Edmonds|1991|pp=345–346}} The battle was also costly for the Germans, who lost more than {{nowrap|1,000 prisoners.}}{{sfn|Boraston|1920|p=130}} The German 195th Division at Passchendaele suffered {{nowrap|3,325}} casualties from 9 to 12 October and had to be relieved by the 238th Division.{{sfn|Sheldon|2007|p=236}} Ludendorff became optimistic that Passchendaele Ridge could be held and ordered the 4th Army to stand fast.{{sfn|Sheldon|2007|p=233}} On 18 October, Kuhl advocated a retreat as far to the east as possible; Sixt von Armin and Loßberg wanted to hold on, because the ground beyond the Passchendaele [[Drainage divide|watershed]] was untenable, even in winter.{{sfn|Terraine|1977|p=305}}

==== Action of 22 October ====
{{main|Action of 22 October 1917}}

On 22 October the 18th (Eastern) Division of XVIII Corps attacked the east end of Poelcappelle as XIV Corps to the north attacked with the 34th Division between the Watervlietbeek and Broenbeek streams and the 35th Division northwards into [[Houthulst]] Forest. The attack was supported by a regiment of the French 1st Division on the left flank of the 35th Division and was intended to obstruct a possible German counter-attack on the left flank of the Canadian Corps as it attacked Passchendaele and the ridge. The artillery of the Second and Fifth armies conducted a bombardment to simulate a general attack as a deception. Poelcappelle was captured but the attack at the junction between the 34th and 35th divisions was repulsed. German counter-attacks pushed back the 35th Division in the centre but the French attack captured all its objectives. Attacking on ground cut up by bombardments and soaked by rain, the British had struggled to advance in places and lost the ability to move quickly to outflank pillboxes. The 35th Division reached the fringe of Houthulst Forest but was outflanked and pushed back in places. German counter-attacks made after 22 October, were at an equal disadvantage and were costly failures. The German 4th Army was prevented from transferring troops away from the Fifth Army and from concentrating its artillery-fire on the Canadians as they prepared for the Second Battle of Passchendaele (26 October – 10 November 1917).{{sfn|Perry|2014|pp=475–486}}

====Battle of La Malmaison====

{{Main|Battle of La Malmaison}}

After numerous requests from Haig, Petain began the Battle of La Malmaison, a long-delayed French attack on the Chemin des Dames, by the Sixth Army (General [[Paul Maistre]]). The artillery preparation started on 17 October and on 23 October, the German defenders were swiftly defeated and the French advanced up to {{cvt|3.7|mi}}, capturing the village and fort of La Malmaison, gaining control of the Chemin des Dames ridge.{{sfn|Terraine|1977|p=307}} The Germans lost {{nowrap|38,000 men}} killed or missing and {{nowrap|12,000 prisoners,}} along with {{nowrap|200 guns}} and {{nowrap|720 machine-guns,}} against {{nowrap|14,000 French}} casualties, fewer than a third of the German total.{{sfn|Philpott|2014|p=279}} The Germans had to withdraw from their remaining positions on the Chemin des Dames to the north of the Ailette Valley early in November. Haig was pleased with the French success but regretted the delay, which had lessened its effect on the Flanders operations.{{sfn|Terraine|1977|p=307}}

====Second Battle of Passchendaele====

{{Main|Second Battle of Passchendaele}}

[[File:Second Battle of Passchendaele - Barbed wire and Mud.jpg|thumb|{{centre|Terrain through which the Canadian Corps advanced at Passchendaele, in late 1917}}]]
[[File:Landscape Passendale Tyne Cot 2.jpg|thumb|{{centre|Terrain at Passchendaele near where the Canadian Corps advanced, spring 2015}}]]
The British [[Fifth Army (United Kingdom)|Fifth Army]] undertook minor operations from {{nowrap|20 to 22 October,}} to maintain pressure on the Germans and support the French attack at La Malmaison, while the Canadian Corps prepared for a series of attacks from {{nowrap|26 October to 10 November.}}{{sfnm|1a1=Bean|1y=1941|1p=930|2a1=Edmonds|2y=1991|2p=347}} The four divisions of the Canadian Corps had been transferred to the [[Ypres Salient]] from Lens, to capture Passchendaele and the ridge.{{sfn|Bean|1941|p=929}} The Canadians relieved the [[II Anzac Corps]] on 18 October and found that the front line was mostly the same as that occupied by the [[1st Canadian Division]] back in April 1915. The Canadian operation was to be three limited attacks, on 26 October, 30 October and 6 November.{{sfn|Nicholson|1964|pp=312, 314}} On 26 October, the 3rd Canadian Division captured its objective at Wolf Copse, then swung back its northern flank to link with the adjacent division of the Fifth Army. The 4th Canadian Division captured its objectives but was forced slowly to retire from Decline Copse by German counter-attacks and communication failures between the Canadians and the Australian units to the south.{{sfn|Nicholson|1964|p=320}}

The second stage began on 30 October, to complete the previous stage and gain a base for the final assault on Passchendaele. The attackers on the southern flank quickly captured Crest Farm and sent patrols beyond the final objective into Passchendaele. The attack on the northern flank again met with exceptional German resistance. The 3rd Canadian Division captured Vapour Farm on the corps boundary, Furst Farm to the west of Meetcheele and the crossroads at Meetcheele but remained short of its objective. During a seven-day pause, the Second Army took over another section of the Fifth Army front adjoining the Canadian Corps. Three rainless days from {{nowrap|3 to 5 November}} eased preparation for the next stage, which began on the morning of 6 November, with the 1st Canadian Division and the [[2nd Canadian Division]]. In less than three hours, many units reached their final objectives and Passchendaele was captured. The Canadian Corps attacked on 10 November to gain control of the remaining high ground north of the village near {{nowrap|Hill 52.}}{{sfnm|1a1=Nicholson|1y=1964|1pp=320–325|2a1=Sheldon|2y=2007|2pp=311–312}}{{efn|German troops engaged were from the 239th, 39th, 4th, 44th Reserve, 7th, 11th, 11th Bavarian, 238th, 199th, 27th, 185th, 111th and 40th divisions.{{sfn|USWD|1920}}}}

===December===

====Night action of 1/2 December 1917====

{{main|Night action of 1/2 December 1917}}

On 18 November the VIII Corps on the right and II Corps on the left (northern) side of the Passchendaele Salient took over from the Canadian Corps. The area was subjected to constant German artillery bombardments and its vulnerability to attack led to a suggestion by Brigadier C. F. Aspinall, that either the British should retire to the west side of the Gheluvelt Plateau or advance to broaden the salient towards Westroosebeke. Expanding the salient would make the troops in it less vulnerable to German artillery-fire and provide a better jumping off line for a resumption of the offensive in the spring of 1918. The British attacked towards Westroozebeke on the night of 1/2 December but the plan to mislead the Germans by not bombarding the German defences until eight minutes after the infantry began their advance came undone. The noise of the British assembly and the difficulty of moving across muddy and waterlogged ground had also alerted the Germans. In the moonlight, the Germans had seen the British troops when they were still {{cvt|200|yd}} away. Some ground was captured and about {{nowrap|150 prisoners}} were taken but the attack on the redoubts failed and observation over the heads of the valleys on the east and north sides of the ridge was not achieved.{{sfn|LoCicero|2011|pp=155–338}}

====Action on the Polderhoek Spur====

{{main|Action on the Polderhoek Spur}}

The attack on the Polderhoek Spur on 3 December 1917, was a local operation by the British [[Fourth Army (United Kingdom)|Fourth Army]] (renamed from the Second Army on 8 November). Two battalions of the [[2nd Infantry Brigade (New Zealand)|2nd New Zealand Brigade]] of the [[New Zealand Division]] attacked the low ridge, from which German observers could view the area from Cameron Covert to the north and the Menin road to the south-west. A New Zealand advance of {{cvt|600|yd}} on a {{cvt|400|yd}} front, would shield the area north of the Reutelbeek stream from German observers on the Gheluvelt spur. Heavy artillery bombarded the ruins of Polderhoek Château and the pillboxes in the grounds to mislead the defenders and the attack was made in daylight as a ruse to surprise the Germans, who would be under cover sheltering from the routine bombardments. Smoke and gas bombardments on the Gheluvelt and Becelaere spurs on the flanks and the infantry attack began at the same time as the "routine" bombardment. The ruse failed, some British artillery-fire dropped short on the New Zealanders and the Germans engaged the attackers with small-arms fire from Polderhoek Spur and Gheluvelt ridge. A strong west wind ruined the smoke screens and the British artillery failed to suppress the German machine-guns. New Zealand machine-gunners repulsed a counter-attack but the New Zealand infantry were {{cvt|150|yd}} short of the first objective; another attempt after dark was cancelled because of the full moon and the arrival of German reinforcements.{{sfn|Stewart|2014|pp=304–314}}