“Battle of Hill 70”的意思、由来-开放百科全书

The Battle of Hill 70 took place in World War I between the Canadian Corps and four divisions of the German 6th Army. The battle took place along the Western Front on the outskirts of Lens in the Nord-Pas-de-Calais region of France between 15 and 25 August 1917.

The objectives of the assault were to inflict casualties and to draw German troops away from the 3rd Battle of Ypres and to make the German hold on Lens untenable.{{sfn|Cook|2000|p=125}} The Canadian Corps executed an operation to capture Hill 70 and then establish defensive positions from which combined small-arms and artillery fire, some of which used the new technique of predicted fire, would repel German counter-attacks and inflict as many casualties as possible. The goals of the Canadian Corps were only partially accomplished; the Germans were prevented from transferring local divisions to the Ypres Salient but failed to draw in troops from other areas.{{sfn|Cook|2000|p=132}}

A later attempt by the Canadian Corps to extend its position into the city of Lens failed but the German and Canadian assessments of the battle concluded that it succeeded in its attrition objective. The battle was costly for both sides and many casualties were suffered from extensive use of poison gas, including the new German Yellow Cross shell containing the blistering agent sulphur mustard (mustard gas).

Background

Western front

By May 1917, the Nivelle Offensive, despite the successful opening of the Battle of Arras, had come to a disastrous conclusion with the French Army mutinies.{{sfn|Delaney|2016|pp=6–10}} On 30 April, as the French hesitated to continues the Second Battle of the Aisne (16 April – 9 May 1917), the commander of the British Expeditionary Force, Field Marshal Sir Douglas Haig, gave orders to the First Army (General Henry Horne), to advance towards Lens to gain a line from Méricourt to Sallaumines Hill, Lens and Hill 70. Horne already desired to cut off the salient containing Lens, to shorten the front, while unwilling to risk a costly and slow frontal assault into the maze of ruins. The First Army was understrength after the Battle of Arras but after the German withdrawal to the Hindenburg Line in March, there was some hope that the 6th Army (General Otto von Below) could be manoeuvred out of Lens by a gradual advance to capture the higher ground to the south, west and north of the city.{{sfn|Humphries|2016|pp=80–81}}

On 7 May, Haig informed the British army commanders that the French had terminated the Nivelle Offensive and the strategy of returning to a war of manoeuvre. Operations to exhaust the powers of resistance of the German armies would resume by systematic surprise attacks and when this was complete, the British would begin an offensive at Ypres to capture the Belgian coast and reach the frontier with the Netherlands.{{sfn|Humphries|2016|pp=80–81}} The objectives of the First Army were unchanged but instead of capturing ground around Lens to shorten the front, the intention was to menace the German hold on Lens and the defences south of Lille, to distract, divert and weaken the defenders. The operations were not a diversion but a means to keep the First Army front active for as long as possible, to mislead the Germans as to British intentions in Flanders.{{sfn|Humphries|2016|pp=80–81}} On 8 May, Horne told the corps commanders that

Lens

From Vimy Ridge the ground declines about {{convert|300|yd|m|abbr=on}} into the Douai Plain; the valley of the Souchez river is about {{convert|20|m|yd|order=flip|abbr=on}} wide and flows south-west to north-east through the south of the city of Lens. In 1914, the river had been crossed by several road and rail bridges. By 1917, much of the city was derelict due to years of artillery bombardments, the ruins being natural strongpoints overlooked by crassiers (slag heaps) and several hills, including Hill 70, Hill 65 and Sallaumines Hill. The city is in a shallow, saucer-shaped depression surrounded by the crassiers and hills. To the south-east, on terrain that is {{convert|25|to|45|m|ft|order=flip|abbr=on}} above sea level, Sallaumines Hill rises to {{convert|55|m|ft|order=flip|abbr=on}}. On the west side of Lens is Hill 65 (Reservoir Hill) north of the Souchez, which is steep-sided and gives a fine view of the city.{{sfn|Humphries|2016|pp=79–80}}

To the north-west, on the east side of the Lens–Bethune road is a hill about {{convert|70|m|ft|order=flip|abbr=on}} high with the suburb of Cité St Pierre on top. Hill 70 is north of the city and has a flat top, giving a fine view of the city and the ground to the north and east. The hill slopes gently towards Lens and there is a shallow depression between it and Cité St Pierre. The slopes of Hill 70 towards Cité St Auguste are steeper.{{sfn|Humphries|2016|pp=79–80}} Lens, Hill 70, Sallaumines Hill to the south-east an their commanding views over the area and the city, had fallen under German control in October 1914, during the Race to the Sea.{{sfn|Burg|Purcell|2004||p=29}} In September 1915, the British had overrun the hill during the Battle of Loos but had not managed to hold it.{{sfn|Farr|2007|p=171}}

Local operations

Horne began to make plans for the capture of Lens during the Third Battle of the Scarpe (3–4 May). Horne wanted the Canadian Corps to continue its operations east of Vimy Ridge to capture Méricourt and La Coulotte, which would endanger the German defences of Sallaumines Hill, south-east of Lens, as I Corps (Lieutenant-General Arthur Holland) north of the Souchez, with twelve tanks, captured Hill 65 (Reservoir Hill) and Hill 70. The attacks would envelop Lens on three sides and give forward observation officers (FOO) sight of the German defences in the city, potentially to force the 6th Army to retire without the need for a frontal attack. In May, Holland had surveyed the I Corps front, noted that the tactical value of Hill 70 and that it would be inevitable that the Germans would make great efforts to re-capture the hill. German counter-attacks could only be resisted if plenty of reserves and much artillery support were made available. Deliberate attacks to capture the high ground around Lens would meet the goals of the First Army despite its limited means.{{sfn|Humphries|2016|pp=80, 82}} In May and early June, First Army units conducted eighteen raids and minor actions, moving the front line slowly eastwards over the Douai Plain. By 6 June, the First Army had captured all the high ground in the area, except that around Lens. I Corps was west of the city from the Souchez north to Hill 65 (Reservoir Hill), through Cité St Theodore and along the ridge of the 70-metre hill to the north of Cité St Pierre.{{sfn|Humphries|2016|pp=82}}

On 9 June, the commander of the Canadian Corps, Lieutenant-General Julian Byng was promoted and assumed command the Third Army. Arthur Currie, the 1st Canadian Division commander, was promoted in his place.{{sfn|Granatstein|2004|pp=118–119}} On 10 June, Holland told Horne that only the capture of Hill 70 was important and suggested inflicting mass casualties by raids, bombardments and gas attacks, to create the impression that a big attack was imminent. The defenders would be subjected to anxiety and have to move more troops and artillery to the hill, despite the inevitable losses. Horne doubted that the army had sufficient men and artillery for the task and arranged for the 46th (North Midland) Division, on the right of I Corps, to make preparations to take Hill 70 and the vicinity but only if reinforcements from GHQ were forthcoming. While waiting, I Corps would capture Hill 65 and south of the Souchez, XIII Corps and the right hand divisions of the Canadian Corps would prepare to attack from Gavrelle to Oppy, Fresnoy, Acheville and Mėricourt, digging jumping-off trenches to simulate a threat to Lens from the south. The real attack was to come from the left flank of the Canadian Corps towards Sallaumines Hill and the east end of Avion. Success would trap the Germans in Lens between Sallaumines Hill to the south and Hill 70 to the north. If the 6th Army did not retire, the preparations by I Corps at Hill 70 would make it impossible to predict from which direction the next attack would come.{{sfn|Humphries|2016|p=83}}

Affairs south of the Souchez

To create a threat to Lens, Horne intended that XIII Corps on the southern flank would attack to reach better positions between the villages of Gavrelle and Oppy by advancing the front line for {{convert|200|to|500|yd|m|abbr=on}} on a {{convert|2300|yd|m|abbr=on}} front. The 4th Canadian Division on the left flank of the Canadian Corps south of the Souchez river (a tributary of the Deûle) and the 46th (North Midland) Division on the right of I Corps, north of the river, were to attack on a front of {{convert|4800|yd|m|abbr=on}} to eliminate a German salient from Avion to the west end of Lens and to occupy Hill 65 (Reservoir Hill). I Corps was to plan for an attack on Hill 70 with the 6th Division on the left (northern) flank. Horne expected that the operations would take place in early July but found that many of the best heavy guns were to be sent to Flanders and brought forward the date to 28 June. The plans were made less ambitious; the XIII Corps scheme was retained but the attack either side of the Souchez was reduced to the capture the German front line west of Avion and Hill 65; the Hill 70 plan was postponed.{{sfn|Edmonds|1991|pp=112–113}}

28 June was dull, humid and storm clouds appeared in the south over the afternoon. The First Army artillery, assisted by Third Army guns en route to Flanders, began a bombardment along the {{convert|14|mi|km|abbr=on}} army front from Gavrelle to Hulluch. The simulation of a much bigger attack on Lens was enhanced by lightning, thunder and a downpour, which began at {{nowrap|7:10 p.m.}} when the infantry advance began. The adjacent brigades of the 31st and 5th divisions had been bombarded in their jumping-off trenches at {{nowrap|5:30 p.m.}} and suffered 200 casualties before the advance began. The survivors moved so fast that when a German counter-barrage fell on no man's land three minutes later, the British were on the far side and unharmed. The attackers suffered few casualties, took {{nowrap|200 prisoners}} and counted {{nowrap|280 dead}} German soldiers. Gavrelle Mill and a new line was consolidated, despite the rainstorm, from which the areas to the north-east and east around Neuvireuil and Fresnes could be observed, along with Greenland Hill to the south-west.{{sfn|Edmonds|1991|pp=113–114}}

Capture of Avion

Orders from the First Army HQ reached Currie on 12 June, who replied with a suggestion that the capture of Hill 65 was tactically desirable to gain observation over Lens and to deprive the Germans of reciprocal observation of the British rear. The capture of Avion could be replaced by a raid, to avoid the casualties of a permanent occupation. Preparations for offensive operations towards Avion would be more meaningful to German observers than the attack which followed. The suggested alternative was not well received by Major-general W. H. Anderson, the First Army chief of staff, because one purpose of the operation was to threaten Lille, which could only occur with the capture of Lens, after the attack on Avion. The Canadian operation was only a stage in the plan, to be followed by an attack or decoy towards Sallaumines Hill. A few days later more artillery was transferred to Flanders, which led to the postponement of the Hill 70 attack.{{sfn|Humphries|2016|pp=85–86}}

Further north, opposite the 4th Canadian and 46th (North Midland) divisions, the German 56th Division had on 22 June, moved into reserve to substitute for a division transferred to Flanders. The division holding the line had orders to retire from the salient to the Avion–Lens railway if pressed. The western slopes of Hill 65 had been occupied on 24 June after a German retirement and patrols pushed forward towards Avion Trench, which was taken early on 28 June. The divisions made ready to resume the advance when the army barrage began at {{nowrap|7:10 p.m.}} Most of Avion, Éleu-dit-Leauwette and the eastern slope of Hill 65 was captured, as the 3rd Canadian Division formed a defensive flank along the Arleux–Avion road, joining with the 4th Canadian Division in Avion. Rain and the flooding from the Souchez stopped patrols from probing the German main line of resistance in the north-eastern part of Avion and along a railway embankment about {{nowrap|600|yd|m|abbr=on}} further on.{{sfn|Edmonds|1991|pp=114–115}}

Prelude

Plan

On 7 July, due to a lack of artillery Currie was ordered to take over more of the line to the north to attack the objectives west of Lens not taken by the 46th (North Midland) Division from 29 June and 2 July and in the south to attack beyond Avion to a railway embankment, ready to advance to Sallaumines Hill. Soon afterwards, GHQ announced that more artillery would be forthcoming and Horne met the corps commanders again on 10 July, where Currie wanted to make the main effort north of the Souchez, the Canadian Corps taking responsibility for the front from Avion to Hill 70. Horned agreed and on 11 July, Currie issued the first orders for the attack. The Canadian plan for 30 July used the I Corps plan for a June attack as a basis and the scheduled attack to the embankment east of Avion was to go ahead to simulate preparations to obtain a good jumping off point for a later advance on Sallaumines Hill. From 11 to 19 July, Canadian Corps intelligence discovered that German dispositions had changed. A new third defensive line along the northern outskirts of the city from Cinnabar Trench along Nun's Alley, Norman Trench, Hugo Trench to Bois Hugo had been completed and lay beyond the objectives given to Currie on 10 July. The position had three belts of barbed wire, a light railway for supply and eleven strongpoints with fields of fire into Commotion Trench, the final Canadian objective and was judged to be the new main German defence line.{{sfn|Humphries|2016|pp=87–89}}

The capture of Hill 70 would provide excellent observation over the German lines, in preparation for more offensives. Currie believed the Germans would attempt to counter-attack if Hill 70 were captured, largely because of its observational importance and that the advantageous artillery observation would defeat German counter-attacks with accurate artillery-fire.{{sfn|Nicholson|1962|p=285}} The plan was therefore to occupy the high ground quickly, establish strongpoint defensive positions around the {{nowrap|48 Vickers machine guns}} allocated to each brigade and use combined small-arms and artillery-fire to repel counter-attacks and inflict as many casualties as possible.{{sfn|Bell|1992|pp=74–75}}{{sfn|Walthert|2015|p=23}} The 1st and 2nd Canadian Divisions to attack on a front of {{convert|4000|yd|mi+km|abbr=on}}. Their objective was to capture the main enemy defensive positions on the eastern or reverse slope of Hill 70. The objectives were marked off in depth by three stages. In the first stage, the assaulting troops would capture the German front-line trenches. The German second position on the crest of the hill during the second stage and the final stage, marked by the German third line, on the reverse side of the slope, some {{convert|1500|yd|m}} from the starting position. The 1st Canadian Division's 3rd Canadian Infantry Brigade would attack north of Hill 70 while the 2nd Canadian Infantry Brigade would attack the summit.{{sfn|Bell|1992|p=75}} The 2nd Canadian Division's 4th and 5th Canadian Infantry Brigades would attack the ruined suburbs of Cité St. Édouard, St. Laurent and St. Émile directly south of Hill 70.{{sfn|Nicholson|1962|pp=287–288}}

Deceptions

By 16 July, the Canadian Corps had redeployed for the attack on Hill 70, the 1st Canadian Division having taken over from I Corps to the north-west of the hill, for the corps to occupy the line from the Souchez northwards to just beyond Hill 70. To deceive the Germans about the place and size of the attack being prepared and to disguise the Canadian preparations, the four corps (XIII, Canadian, I and XI) began to conduct larger raids in battalion strength on most nights from the middle of July, along with gas discharges. Towards the end of the month, raids and bombardments on the army front increased, XI Corps to the north raided nightly, I Corps conducted destructive and wire-cutting bombardments at night and bombarded the German front with machine-guns and mortars during the day; XIII Corps conducted similar operations on the right (southern) army flank.{{sfn|Nicholson|1962|p=285}}{{sfn|Gardner|2016|pp=39–40}}

In late July, the 9th Canadian Brigade feinted a direct attack of Lens by engaging units of the German 36th Reserve Division at Mericourt Trench.{{sfn|Nicholson|1962|p=285}}{{sfn|Farr|2007|p=171}}{{sfn|Walthert|2015|p=23}} Bad weather led to the postponement of the attack on Hill 70 from late July until mid-August. In the interim, special companies of the Royal Engineers augmented the regular level of harassment by firing a total of {{nowrap|3,500 gas}} drums and {{nowrap|900 gas}} shells into Lens by 15 August. The artillery neutralized {{nowrap|40 out}} of an estimated {{nowrap|102 German}} batteries in the area by zero hour, partly using the technique of predicted fire for the first time, using datum points and calibrated guns, which greatly improved the accuracy of the artillery.{{sfn|Farndale|1986|p=205}} Troops were rotated through the reserve area to conduct training and rehearsals in preparation for the assault..{{sfn|Nicholson|1962|p=286}} To the north, the 46th (North Midland) Division set up a diversionary attack north of Hill 70, with poison gas discharges, artillery bombardments and the preparation of dummy tanks and troops on the two nights before the attack, to be exposed to view at zero hour.{{sfn|Gardner|2016|pp=39–40}}

Royal Flying Corps

On 9 August, six Nieuport 17s of 40 Squadron, Royal Flying Corps (RFC) made a low-level attack on the six German observation balloons along the Hill 70–Lens front and shot them down. German observation was reduced but the attack made the Canadian interest in the area obvious. For the two days and nights before the attack, 10, 25 and 27 squadrons bombed railway junctions, airfields and billets. In earlier battles, British fighters patrolling at height to engage German fighters had not been able to see low-flying, camouflaged German aircraft, which flew artillery-observation and ground attack sorties without interference. Six Nieuport 17s of 40 Squadron moved to an advanced landing ground at Mazingarbe about {{convert|5|mi|km|abbr=on}} behind the front and a ground station was established on higher ground west of Loos. When observers spotted a German aircraft at low altitude, a wireless message was sent to Mazingarbe for a Nieuport 17 to be sent up to engage the German aircraft. A letter-code on white canvas sheets containing the location of German aircraft could be laid on the ground for an airborne fighter pilot to read.{{sfn|Wise|1981|p=422}}

The RFC provided 16, 40 and 43 squadrons to support the Canadian Corps and the Sopwith Camels of 8 (Naval) Squadron, Royal Naval Air Service were provided to fly higher over the battlefield. An advanced landing ground at Petit Sains was made ready for 43 Squadron to mount continuous, counter-attack reconnaissance patrols. Formations of three Sopwith 1½ Strutters were to observe an area {{convert|7000|yd|mi+km|abbr=on}} wide and {{convert|1,500|to|2500|yd|mi+km|abbr=on}} deep, that counter-attacking German troops would have to traverse. The Sopwith crews were to report their observations by wireless to the Canadian Corps and heavy artillery headquarters, then attack with their machine-guns any German artillery or concentrations of troops seen at bottlenecks. Contact patrols to mark the progress of the Canadian infantry were to be flown by 16 Squadron.{{sfn|Wise|1981|p=422}}{{sfn|Edmonds|1991|p=221}}

Opposing forces

The Canadian Corps (Lieutenant-General Arthur Currie) had the 1st, 2nd and 4th Canadian divisions for the attack and the 3rd Canadian Division in reserve. Extra artillery brigades were attached to the Canadian divisions, the 14th Army Brigade, Royal Field Artillery (RFA) to the 1st Canadian Division, the 46th Divisional Artillery to the 2nd Canadian Division and the 179th Army Brigade RFA to the 4th Canadian Division. Three heavy artillery groups were under command for counter-battery fire and there were four siege artillery groups.{{sfn|Engen|2016|pp=257–267}}{{sfn|Edmonds|1991|p=221}}

The 6th Army was responsible for the defence of the area between Lille and Cambrai, Lens being about half-way between. The town was an important railway junction and after the Battle of Arras early in 1917, had become a salient in the German defences. Hill 70 and the vicinity was held by the 7th Division, part of {{lang|de|Gruppe Loos}}, the headquarters of IV Corps. (The German army had begun to use corps headquarters as territorial command units, rather than for a permanent complement of divisions.){{sfn|Edmonds|1991|loc=p. 226 (footnote)}} Lens was garrisoned by the 11th Reserve Division in {{lang|de|Gruppe Souchez}} (VI Corps). In anticipation of an attack, Army Group Crown prince Rupprecht had moved the 4th Guard Division and the 220th Division into the 6th Army area in reserve. The divisions in reserve rehearsed reinforcement and counter-attacks with the two front divisions, Below having written of an expected Canadian ({{lang|de|Angriffstruppe}}) attack on 15 July.{{sfn|Foley|2016|p=188}}{{efn|Neighbouring units provided supporting artillery fire and the 49th Reserve Division, 39th Division and the 240th Division moved into reserve at times between 20 and 25 August.{{sfn|Foley|2016|p=197}}}}

Battle

15 August

The assault began at {{nowrap|4:25 a.m.}} on the morning of 15 August, just as dawn was breaking. Special companies of the Royal Engineers fired drums of burning oil into the suburb of Cité St. Élisabeth and at other selected targets to supplement the artillery creeping barrage and build up a smoke-screen. Divisional field artillery positions executed a creeping barrage directly in advance of the assaulting troops while field howitzers shelled German positions {{convert|400|m|yd|abbr=on}} in advance of the creeping barrage and heavy howitzers shelled all other known German strong-points. Artillery Forward Observation Officers moved forward with the infantry and artillery observation aircraft flew overhead and sent {{nowrap|240 calls}} for artillery fire by wireless.{{sfn|Farndale|1986|p=205}} The Germans had moved up their reserve units on the previous night in anticipation of an attack and the main assembly of Canadian troops was detected by {{nowrap|3:00 a.m.}}{{sfn|Nicholson|1962|pp=287–289}}

Within three minutes of the attack commencing, the German artillery brought down defensive fire at widely scattered points. The affected forward positions of the German 7th Division and 11th Reserve Division were quickly overwhelmed. Within twenty minutes of the attack beginning, both Canadian divisions had reached their first objective. By {{nowrap|6:00 a.m.}} the 2nd Canadian Infantry Brigade had reached the second objective line, while units of the three other brigades had in some cases already reached their final objective. Only the flanking companies of the two battalions attacking Hill 70 managed to reach their objectives. The remainder of the both units were forced to retreat up the slope and consolidate their position at the intermediate objective line.{{sfn|Nicholson|1962|pp=287–289}}

On the right flank of the 2nd Canadian Division, the 12th Canadian Infantry Brigade of the 4th Canadian Division executed a diversionary operation which proved successful in drawing German retaliatory fire away from the main operation. Four hours later, the 11th Canadian Infantry Brigade of the 4th Canadian Division attempted to exploit the weakened German force by pushing strong patrols towards the centre of Lens. This ultimately failed as the Germans used local counter-attacks across the 4th Canadian Division's front to drive the patrols back to the city's outskirts.{{sfn|Nicholson|1962|p=289}}

Air operations

The Sopwith {{nowrap|1½ Strutters}} of 43 Squadron received many hits from ground fire but only two were shot down, three crew being wounded; a German aircraft was shot down and others driven off but four more {{nowrap|1½ Strutters}} were too badly damaged to be serviceable for 16 August. One Sopwith attacked troops in Drocourt Trench, another aircraft attacked a transport column near Fouquières, then troops near Annay and in Bois de Quatorze. About {{nowrap|1,600 German}} infantry behind Bois de Dixhuit, north of Lens, were strafed, then the information was reported from Mazingarbe to the Canadian Corps heavy artillery, which dispersed the German troops. While flying artillery-observation sorties in the afternoon, 16 Squadron aircrew saw four waves of German infantry advancing in the open to counter-attack. The crews called on the Canadian heavy artillery and attacked with machine-guns, which "all but annihilated" the German force.{{sfn|Wise|1981|pp=422–423}} From 15 to 17 August, the RFC sent {{nowrap|240 reports}} of German artillery in action and all were answered by the counter-battery groups.{{sfn|Edmonds|1991|p=221}}

Counter-attacks

In preparation for German counter-attacks, the 1st and 2nd Canadian Divisions began to reverse captured trenches and construct strong points immediately after capturing the first objective line. Within two hours of the start of the battle, the Germans began using their immediate reserves to mount local counter-attacks ({{lang|de|Gegenstoße}}).{{sfn|Cook|2000|p=129}} Between {{nowrap|7:00 a.m. and 9:00 a.m.}} on the morning of 15 August, the Germans executed four local attacks against Canadian positions. Each attack was repulsed due in large part to the work of forward artillery observers, who could now overlook some of the German positions. On one occasion, the counter-attack was only repulsed after engaging in hand-to-hand fighting.{{sfn|Cook|2000|p=129}} The Germans rapidly brought up seven additional battalions from the 4th Guards Division and 185th Division to reinforce the eight line battalions already in place. Over the following three days, the Germans executed no less than 21 counter-attacks against Canadian positions.{{sfn|Cook|2000|p=131}} A frontal attack against the 2nd Canadian Infantry Brigade on the afternoon of 15 August ultimately failed. A German attack against the 4th Canadian Infantry Brigade was initially successful with the Germans re-capturing Chicory Trench but were repulsed later the same afternoon.{{sfn|Nicholson|1962|pp=289–290}}

16 August

The morning of 16 August was relatively quiet, with only a few attempts made by small German parties to approach the Canadian lines. After having failed to capture all their objectives the previous day and having postponed additional attacks a number of times, the 2nd Canadian Brigade attacked and captured the remainder of its final objective line on the afternoon of 16 August. The assault lasted a little over an hour but the troops were then forced to defend against a dozen German counter-attacks during the day.{{sfn|Cook|2000|p=130}}{{sfn|Nicholson|1962|pp=290–291}}

Attempts by the 4th and 11th Canadian Infantry Brigades to eliminate a German salient between Cité St Élisabeth and Lens on 17 August failed and as had been foreseen, the Germans continued to mount determined counter-attacks. The German commanders realized that the Canadian and British artillery would need to be neutralized before a counter-attack could succeed. The Germans began a series of counter-attacks against a chalk quarry under Canadian control outside Cité St. Auguste and tried to mislead the Canadian artillery by sending up false flare signals or provoking the infantry to call for unnecessary artillery fire.{{sfn|Cook|2000|p=130}}

The Germans began to use poison gas in earnest and from 15,000 to 20,000 of the new Yellow Cross shells, containing the blistering agent sulphur mustard, were fired in addition to an undetermined number of shells containing diphosgene. The positions of the 1st and 2nd Canadian Artillery Field Brigades and the Canadian front line were heavily gassed. Many gunners became casualties after gas fogged the goggles of their respirators and they were forced to remove them to set fuses, lay their sights and maintain accurate fire.{{sfn|Cook|2000|p=130}}

17–18 August

On the night of {{nowrap|17/18 August,}} German troops made several attempts to recapture the chalk quarry and Chicory Trench under the cover of gas. All attempts against the chalk quarry failed and only one company of the 55th Reserve Infantry Regiment (on loan to the 11th Reserve Division) managed to breach the Canadian defences at Chicory Trench before being repulsed. German troops employing flamethrowers managed to penetrate the Canadian line north of the quarry on the morning of 18 August before being driven out.{{sfn|Nicholson|1962|pp=291–292}}

19–20 August

The front quietened significantly after the final counter-attack against the chalk quarry. For the Canadian Corps, the following two days consisted largely of consolidation. The front line was drawn back {{convert|300|yd|m|abbr=on}}, midway between the original intermediate and final objectives. The 4th Canadian Division slightly advanced its forward posts on the outskirts of Lens and extended its front northward to include the Lens–Béthune road. Currie wished to further improve the position around Hill 70 and ordered an attack against German positions along a {{convert|3000|yd|mi+km|abbr=on}} front, opposite the 2nd and 4th Canadian Divisions.{{sfn|Nicholson|1962|p=293}}

21–22 August (Attack on Lens)

The operation was scheduled for the morning of 21 August, the tasks being divided between the 6th Canadian Infantry Brigade on the left and the 10th Canadian Infantry Brigade on the right. The attack was to begin at {{nowrap|4:35 a.m.}} but the Germans began shelling the Canadian positions at {{nowrap|4:00 a.m.}} Just before the Canadian attack, the left flank of the 6th Canadian Infantry Brigade was attacked by units of the 4th Guard Division and a battalion of the 220th Division. The forces met between their objectives and fought hand-to-hand and with the bayonet; in the mélée the 6th Canadian Infantry Brigade advance was stopped and the troops forced back to their start line. Communication between the forward units and brigade headquarters had broken down at the beginning of the attack and could not be restored due to the German bombardment, making it all but impossible to co-ordinate the infantry and artillery.{{sfn|Nicholson|1962|pp=293–295}}

On the right flank, a unit of the 10th Canadian Infantry Brigade suffered a large number of casualties to the German artillery while assembling for the attack and was met with massed artillery and machine-gun fire, near its objective. Only three small parties, the largest of not more than twenty men, reached their goal. The other two attacking units captured their objectives late in the evening, creating a salient in the 4th Canadian Division line. On the evening of 21 August, three parties went forward to bomb the German position from the flanks but were only moderately successful and an attack on 22 August failed to materialize, due to battalion-level misunderstandings. A brigade reserve unit was ordered to remedy the situation by attacking the Green Crassier slag heap and the mine complex at Fosse St Louis. The attack was repulsed, most of the attackers being killed, wounded or taken prisoner. The Germans held on to the area until the beginning of the final German retreat in 1918.{{sfn|Nicholson|1962|pp=294–295}}

Aftermath

Analysis

On 15 August, Haig made a diary note that the attack had gone "very well" and Horne called it "an unqualified success", despite the failure of the 6th Army to retreat and began to plan an attack on Sallaumines Hill for early September.{{sfn|Gardner|2016|p=44}} In 1942, the writers of {{lang|de|Der Weltkrieg}}, the German official history (volume XIII), wrote that since mid-July, the German defences at Lens and for about {{convert|7|km|mi|order=flip||abbr=on}} to the north had been under bombardment, which became more intense in August. Field Marshal Haig wanted to distract from the offensive in Flanders. On 15 August, the Canadian Corps attacked the German positions from Lens to about {{convert|2|km|mi|order=flip||abbr=on}}, took an important height [Hill 70] for observation and pushed beyond the 1st Position ({{lang|de|I Stellung}}). Counter-attacks recapture pockets of ground but the Canadians could not be expelled from {{lang|de|I Stellung}}. Fighting continued intermittently until 24 August but did not lead to more significant changes. The Canadians took over {{nowrap|1,100 prisoners}} and in their counter-attacks the Germans took over {{nowrap|1,002}} prisoners.{{sfn|Reichsarchiv|1942|p=67}}

In 1981, Sydney Wise, author of the Royal Canadian Air Force official history, called the attack at Hill 70 "a demonstration of how a set-piece attack should be carried out".{{sfn|Wise|1981|p=423}} The Germans refrained from attempts to recapture the lost ground at Lens, due to the demands of defensive operations of the Third Battle of Ypres and the need to avoid the diversion of forces from the main effort.{{sfn|Nicholson|1962|p=329}} In 2017, Andrew Rawson wrote that the Canadian attack prevented the Germans from transferring five divisions in the Lens area to Flanders.{{sfn|Rawson|2017|p=120}} In 2016, Robert Foley wrote that Army Group Crown Prince Rupprecht and the 6th Army headquarters thought that the Canadian advance had been stopped by 16 August. Below wrote in his diary that more than ten attacks by the Canadians, "the best English (sic) troops", had been repulsed. The Canadian attack had been stopped because the "English" lacked the flexibility to exploit success, a criticism that had emerged during the Battle of the Somme in 1916.{{sfn|Foley|2016|pp=198–199}}

The Canadian attack was seen as a feint to divert German divisions from Flanders and the army group had ordered the 6th Army to fight with its own resources, including the seven divisions in army reserve. The 4th Guard and the 220th divisions acted as Eingreif divisions on 15 August and with the existing divisions conducted most of the German defence. Once the German counter-attack in 15 August had failed, the attempt to recapture Hill 70 was abandoned and counter-attacks were restricted local efforts to repulse Canadian attacks and for tactical improvements to the German defences. Two divisions were moved from reserve to replace the 4th Guard and the 220th divisions, three more divisions in reserve remaining available to the 6th Army. No forces were transferred to Lens from Flanders or anywhere else and no divisions were sent to Flanders from 15 to 25 August. Foley wrote that the 1st Guard Reserve Division had been included in some accounts but that neither Below or other German sources from the time refer to it; Foley also wrote that Canadian sources mention the 185th Division in interrogation reports.{{sfn|Foley|2016|pp=198–199, 201}}

Casualties

Around 22 August, the First Army intelligence department estimated that Germans suffered {{nowrap|12,000 to 15,000}} casualties.{{sfn|Cook|2016|p=131}} In the History of the Great War (1948), the British official historian, James Edmonds wrote that from 15 to 23 August, the 1st Canadian Division suffered {{nowrap|3,035 casualties}}, {{nowrap|881 being fatal.}} The Second Canadian Division suffered {{nowrap|2,724 casualties,}} {{nowrap|763 men}} being killed and the 4th Canadian Division had {{nowrap|1,432 casualties,}} including {{nowrap|381 killed.}} Corps troops and other troops attached to the 1st Canadian Division suffered {{nowrap|105 casualties,}} a total of {{nowrap|8,418 casualties;}} {{nowrap|1,389 German}} troops were taken prisoner.{{sfn|Edmonds|1991|p=230}} In the Canadian Official History (1962), G. W. L. Nicholson wrote that the Canadians and attached troops suffered {{nowrap|9,198 casualties.}} In Surviving Trench Warfare (1992) Bill Rawling wrote that the attack on Hill 70 cost the Canadian Corps {{nowrap|3,527 casualties,}} {{nowrap|1,056 killed,}} {{nowrap|2,432 wounded}} and {{nowrap|39 taken}} prisoner. In the subsequent attacks into Lens, the Canadian Corps suffered another {{nowrap|5,671 casualties}} increasing the number to {{nowrap|9,198 men}} in eleven days.{{sfn|Rawling|1992|p=142}}

In Capturing Hill 70 (2016, eds. Douglas Delaney and Serge Durflinger) Delaney wrote that Tim Cook remedied a mistake in the Canadian official history which gave Canadian Corps casualties for August rather than for the period 15 to 25 August. Cook calculated that the Canadian Corps suffered about {{nowrap|8,677 casualties}} during the fighting at Hill 70 and Lens. In 2016, Robert Foley wrote that German casualties were difficult to measure, the German official history (Der Weltkrieg) volume noting that complete records did not exist. Foley wrote that the 7th Division suffered about {{nowrap|2,000 casualties}} before being withdrawn on 17 August, the 4th Guard Division about {{nowrap|1,200 from}} 15 to 21 August and that the 220th Division also suffered many casualties, Reserve Infantry Regiment 99 losing {{nowrap|474 men}} in four days. Foley estimated that the Germans suffered {{circa|10,000}} casualties; Delaney and Durflinger wrote that the lower estimates of German casualties were higher than those of the attackers, an unusual occurrence in the war.{{sfnm|1a1=Delaney|1y=2016|1pp=4, 27|2a1=Foley|2y=2016|2pp=190–191|3a1=Delaney|3a2=Durflinger|3y=2016|3p=253}}

Subsequent operations

From the rest of August to the beginning of October the front was relatively quiet, with Canadian efforts devoted mainly to preparations for another offensive, although none took place, largely because the First Army lacked sufficient resources for the task.{{sfn|Nicholson|1962|p=297}} The Canadian Corps was transferred to the Ypres sector in early October in preparation for the Second Battle of Passchendaele.{{sfn|Nicholson|1962|p=312}} Soon after the battle, Below was transferred to the Italian front, where he took command of the new Austro-German 14th Army. In this capacity, he executed an extremely successful offensive at the Battle of Caporetto in October 1917. {{lang|de|General der Infanterie}} Ferdinand von Quast took over command of the 6th Army until the end of the war.{{sfn|Jukes|Simkins|Hickey|2003|pp=54–55}}

Victoria Cross

Six Victoria Crosses, the highest military decoration for valour awarded to British and Commonwealth forces, were awarded to members of the Canadian Corps for their actions during the battle;

Notes

Footnotes

References

External links