Battle of Cambrai (1917)

Cambrai area, 1917

Proposals for an operation in the Cambrai area using a large number of tanks originated from Brigadier Hugh Elles of the Tank Corps, and the reliance on the secret transfer of artillery reinforcements to be "silently registered" to gain surprise came from Henry Hugh Tudor, commander of the 9th (Scottish) infantry division artillery.[7] In August 1917, Tudor conceived the idea of a surprise attack in the IV Corps sector, he suggested a primarily artillery-infantry attack, which would be supported by a small number of tanks, to secure a breakthrough of the German Hindenburg Line. The German defences were formidable; Cambrai, was a quiet front and the Germans had built an elaborate defence in depth.[8]

Tudor's plan sought to test new methods in combined arms, with emphasis on joint artillery and infantry tactics to see how effective they were against German fortifications.[8] Tudor advocated using the new sound ranging and silent registration of guns to achieve instant suppression fire and surprise. He also wanted to use tanks to clear paths through the deep barbed wire obstacles in front of German positions, while supporting the tank force with the No. 106 Fuze, designed to detonate high explosive (HE) ammunition without cratering the ground, to supplement the armour.[9]

Two weeks before the start of the battle, the Royal Flying Corps (RFC) began to train its pilots in ground-attack tactics. Before the ground offensive, the RFC was assigned sets of targets to attack, including trenches, supply points and enemy airfields.[10]

Cambrai salient north, 1917

The battle began at dawn, approximately 06:30 on 20 November, with a predicted bombardment by 1,003 guns on German defences, followed by smoke and a creeping barrage at 300 yd (270 m) ahead to cover the first advances. Despite efforts to preserve secrecy, the Germans had received sufficient intelligence to be on moderate alert: an attack on Havrincourt was anticipated, as was the use of tanks. The attacking force was six infantry divisions of the III Corps (Lieutenant-General Pulteney) on the right and IV Corps (Lieutenant-General Charles Woollcombe) on the left, supported by nine battalions of the Tank Corps with about 437 tanks. In reserve was one infantry division in IV Corps and the three divisions of the Cavalry Corps (Lieutenant-General Charles Kavanagh). Initially, there was considerable success in most areas and it seemed as if a great victory was within reach; the Hindenburg Line had been penetrated with advances of up to 5.0 mi (8 km). On the right, the 12th (Eastern) Division advanced as far as Lateau Wood before being ordered to dig in. The 20th (Light) Division forced a way through La Vacquerie and then advanced to capture a bridge across the Canal de Saint-Quentin at Masnières. The bridge collapsed under the weight of a tank halting the hopes for an advance across the canal.[11] In the centre the 6th Division captured Ribécourt and Marcoing but when the cavalry passed through late, they were repulsed from Noyelles.[12]

The bridge at Masnières, collapsed by the weight of a Mark IV tank

On the IV Corps front, the 51st (Highland) Division (Major-General George Harper) was held at Flesquières, its first objective, which left the attacking divisions on each flank exposed to enfilade fire. Harper had used a local variation of the tank drill instead of the standard one laid down by the Tank Corps.[lower-alpha 2] Flesquières was one of the most fortified points in the German line and was flanked by other strong points. Its defenders under Major Krebs acquitted themselves well against the tanks, almost forty being knocked out by the artillery in the vicinity.[lower-alpha 3] The Lone gunner of Flesquières (a common explanation of the "mythical" German officer) ignored the fact that the British tanks were opposed by a specialist anti-tank unit benefiting from the experience against French tanks in the Nivelle Offensive. The Germans abandoned Flesquières during the night.[16]

Men of the 16th Battalion, Royal Irish Rifles of the 36th (Ulster) Division moving to the front line 20 November 1917

To the west of Flesquières, the 62nd (2nd West Riding) Division swept all the way through Havrincourt and Graincourt to within reach of the woods on Bourlon Ridge and on the British left, the 36th Division reached the Bapaume–Cambrai road. Of the tanks, 180 were out of action after the first day, although only 65 had been destroyed. Of the other casualties, 71 had suffered mechanical failure and 43 had ditched.[17] The British lost c. 4,000 casualties and took 4,200 prisoners, a casualty rate half that of the Third Battle of Ypres (Passchendaele) and a greater advance in six hours than in three months at Flanders but the British had failed to reach Bourlon Ridge.[18] The German command was quick to send reinforcements and was relieved that the British did not manage fully to exploit their early gains.[19] When the battle was renewed on 21 November, the pace of the British advance was greatly slowed. Flesquières, that had been abandoned and Cantaing were captured in the very early morning but in general the British took to consolidating their gains rather than expanding.[20] The attacks by III Corps were terminated and attention was turned to IV Corps.[21]

Cambrai salient south, 1917

The effort was aimed at Bourlon Ridge. Fighting was fierce around Bourlon and at Anneux (just before the woods) was costly.[22] German counter-attacks squeezed the British out of Moeuvres on 21 November and Fontaine on 22 November; when Anneux was taken, the 62nd Division found themselves unable to enter Bourlon Wood. The British were left exposed in a salient. Haig still wanted Bourlon Ridge and the exhausted 62nd Division was replaced by the 40th Division (Major-General John Ponsonby) on 23 November. Supported by almost 100 tanks and 430 guns, the 40th Division attacked into the woods of Bourlon Ridge on the morning of 23 November and made little progress. The Germans had put two divisions of Gruppe Arras on the ridge with another two in reserve and Gruppe Caudry was reinforced.[23]

The 40th Division attack reached the crest of the ridge but were held there and suffered more than 4,000 casualties in three days. More British troops were pushed in to move beyond the woods but the British reserves were rapidly depleted and more German reinforcements were arriving.[24] The final British effort was on 27 November by the 62nd Division aided by 30 tanks. Early success was soon reversed by a German counter-attack. The British now held a salient roughly 6.8 mi × 5.9 mi (11 km × 9.5 km) with its front along the crest of the ridge.[25] On 28 November, the offensive was stopped and the British troops were ordered to lay wire and dig in. The Germans were quick to concentrate their artillery on the new British positions. On 28 November, more than 16,000 shells were fired into the wood.[26]

The German counter-attack

As the British took the ridge, German reinforcements began to arrive. By 23 November, the German command felt that a British breakthrough had been prevented and began to consider a counter-stroke and twenty divisions were assembled in the Cambrai area.[27] The Germans planned to retake the Bourlon salient and also to attack around Havrincourt, with diversionary attacks to hold IV Corps; it was hoped to at least reach the old positions on the Hindenburg Line. The Germans intended to employ the new tactics of a short, intense period of shelling followed by a rapid assault using Hutier infiltration tactics, leading elements attacking in groups rather than waves and bypassing strong opposition. Three divisions of Gruppe Arras (Generalleutnant Otto von Moser) were to conduct the initial assault at Bourlon.[28] On the eastern flank of the British salient, Gruppe Caudry was to attack from Bantouzelle to Rumilly to capture Marcoing.[29] Gruppe Busigny advanced from Banteux. The two Gruppen had seven infantry divisions.[28]

British VII Corps (Lieutenant-General Thomas Snow), to the south of the threatened area, warned III Corps of German preparations. The German attack began at 7:00 a.m. on 30 November; almost immediately, the majority of III Corps divisions were heavily engaged.[lower-alpha 4] The German infantry advance in the south was unexpectedly swift. The commanders of the 12th (Eastern) Division and 29th Division were almost captured, with Brigadier-General Berkeley Vincent having to fight his way out of his headquarters and grab men from retreating units to try to halt the Germans. In the south, the German advance spread across 8.1 mi (13 km) and came within a few miles of the village of Metz and its link to Bourlon.[31]

At Bourlon, the Germans suffered many casualties.[32] British units displayed reckless determination; one group of eight British machine-guns fired over 70,000 rounds against the German advance. The concentration of British effort to hold the ridge was effective but allowed the German advance elsewhere greater opportunity. Only counter-attacks by the Guards Division, the arrival of British tanks and the fall of night allowed the line to be held. By the following day, the impetus of the German advance was lost but pressure on 3 December led to the German capture of La Vacquerie and a British withdrawal on the east bank of the St Quentin canal. The Germans had reached a line curving from Quentin Ridge to near Marcoing. The German capture of Bonavis ridge made the British hold on Bourlon precarious.[33] On 3 December, Haig ordered a partial retreat from the north salient and by 7 December, the British gains were abandoned except for a portion of the Hindenburg line around Havrincourt, Ribécourt and Flesquières. The Germans had exchanged this territorial loss for a slightly smaller sector to the south of Welsh Ridge.[34]

Front lines before and after the battle

The first day of success was greeted in Britain by the ringing of church bells.[35] The massed use of tanks, despite being a further increase on previous deployments, was not entirely new but the success of the attack and the resulting Allied press enthusiasm, including in the United States, were unprecedented.[4] The particular effectiveness of the tanks at Cambrai was the initial passage through barbed wire defences, which had been previously "supposed by the Germans to be impregnable".[36]

The initial British success showed that even the strongest trench defences could be overcome by a surprise attack, using a combination of new methods and equipment, reflecting a general increase in the British capacity to combine infantry, artillery, tanks and aircraft in attacks.[37] The German revival after the shock of the British attack improved German morale but the potential for similar attacks meant that the Germans had to divert resources to anti-tank defences and weapons, an extra demand that the Germans could ill afford to meet,

Wherever the ground offers suitable going for tanks, surprise attacks like this may be expected. That being the case, there can be no more mention, therefore, of quiet fronts.

— Crown Prince Rupprecht[38]

The German counter-attack showed the effectiveness of artillery, trench mortars and evolving stormtrooper tactics, adopted from a pattern introduced by General Hutier against the Russians.[39][37] From the German perspective, questions arose regarding battlefield supply beyond railheads and the suitability of the MG 08 machine gun for rapid movement.[40] By the end of the battle, the British retained some of the ground captured in the north and the Germans a smaller amount taken in the south. The British conducted several investigations, including a Court of Enquiry.[39]

According to the Statistics of the Military Effort of the British Empire during the Great War, British forces in the period of the Battle of Cambrai suffered 75,681 casualties, 10,042 killed or died of wounds, 48,702 wounded and 16,987 missing or prisoners of war.[41] Nearly 180 tanks were destroyed.[42] According to the German Army Medical report in the World War 1914–1918 German forces suffered 54,720 casualties at Cambrai, 8,817 killed and died of wounds, 22,931 wounded and 22,972 missing and prisoners of war.[43] The British recorded casualties on the basis of a daily head count and the Germans counted the number of patients in hospital every ten days, which omitted lightly wounded, expected to return to service in a few days, not evacuated from the corps area.

The Commonwealth War Graves Commission has four Memorials with the names or remains of 9,100 Commonwealth servicemen dead during the Battle of Cambrai:

• Cambrai Memorial to the Missing – the monument lists 7,048[46] missing soldiers of the United Kingdom and South Africa who died and have no known graves.[47]
• Flesquieres Hill British Cemetery – 900 servicemen were buried, one third unidentified.[48]
• Orival Wood Cemetery – 200 servicemen buried.[48]
• Hermies Hill British Cemetery – 1,000 servicemen buried.[48]

The German War Cemetery on the Route de Solesmes was established before the offensive in May 1917, currently it accommodates the remains of 10,685 German and 501 British soldiers.[49]