The Battle of Cambrai, 20 November-7 December 1917, was the first large scale tank battle in history. It was launched after the general failure of the main British autumn offensive of 1917, the Third Battle of Ypres, famous for the Passchendaele mud. Ironically the poor weather at Ypres had preserved the Tank Corps, which by November could field over 300 tanks.
The idea for an attack at Cambrai had been developed by Brigadier General H. Elles, the commander of the Tank Corps. He wanted to launch a mass attack with his tanks across the dry chalky ground at Cambrai, where his tanks wouldn’t run the risk of bogging down in the mud. His plans were received with some enthusiasm by General Sir Julian Byng, commander of the Third Army.
His own artillerymen had also come up with a plan that combined a tank attack with a new type of artillery bombardment that did not require lengthy preparation. Earlier bombardments had required a preliminary period of “registration” in which each gun battery had fired practise rounds to determine where their shots were landing. This alerted the defenders to the possibility of an assault and allowed them to gather reserves. Brigadier General H.H. Tudor had devised a system to register guns electronically, thus avoiding the need for a long period of preparation.
The attack at Cambrai was to be launched by just over 300 tanks spread out along a 10,000 yard front and supported by eight infantry divisions. The infantry were to advance close behind the tanks to provide close support. The artillery bombardment would start on the day of the attack, giving no warning of the upcoming assault.
The artillery bombardment began at 6.20 am on 20 November 1917. The two German divisions at Cambrai, the 20th Landwehr and 54th Reserve divisions, were caught entirely by surprise. Along most of the line the British tanks crawled their way through the German wire, across the trenches, and with close infantry support reached as far as four miles into the German lines.
The position was not so promising in the centre of the British line. The commander of the German 54th Reserve division had prepared anti-tank tactics, based around the use of artillery against slowly moving targets. The infantry of the 51st Highland Division was too far behind the tanks, leaving them vulnerable. Eleven were destroyed in front of the advancing Highlanders. At the end of the first day the British had created a six mile wide gap in the German lines, but with a salient at its centre.
The success at Cambrai on 20 November was treated as a great victory in Britain, where the church bells rang out for the first time since 1914. However, after the great successes of 20 November the advance slowed down. The tanks of 1917 were still not mechanically reliable and many had broken down under the stresses of the advance. Some limited progress was made over the next week, but the defences of the Siegfried line held.
While the British were inching their way forward, the Germans were preparing for a counterattack. On 30 November 20 German divisions under the command of Crown Prince Rupprecht and General von Marwitz launched a massive counterattack that forced the British out of many of the areas they had captured on 20 November and even captured some areas held by the British before the start of the battle. On 4 December Haig ordered a withdrawal from much of the remaining salient to shorten the lines. The battle which had started with such a dramatic breakthrough ended with the restoration of the status quo.
Loses were roughly equivalent on both sides. The British lost 43,000 men, many during the German counterattack. Germans losses were similar, between 40,000 and 50,000 men. The main achievement of the British Tank Corps at Cambrai was to demonstrate all too clearly the potential of the tank. The German tank programme was perhaps their biggest failure of the war. In the crucial battles of 1918 the Germans would have to rely on captured British and French tanks and a very small number of their own dreadful A7V tank.