The First Battle of Cambrai began as British attack on the town of Cambrai and a nearby ridge called Bourlon Ridge. It was an important supply point on the Hindenburg line and the British believed if captured would endanger the German lines. The British decided to make the first large scale use of tanks in the battle.
The battle began on November 20th at 6am in the morning with the traditional artillery barrage. Two infantry divisions supported by nine battalions of tanks(437 tanks) began the advance. Initially the attack went very well and the British believed they were on the verge of complete breakthrough. They successfully penetrated 5 miles into German lines. By the end of first day however, 180 of the tanks that had started the battle were out of action, most due to mechanical failures. Despite their advances the British failed to reach Bourlon Ridge. The German sent reinforcements. The British did not immediately attempt to exploit their breakthrough, but finally on November 27th the British reached the crest of Bourlon Ridge. But they could go no further.
On November 30th the Germans began a counter offensive. At first the Germans made a rapid advance, but soon the British were putting up a strong defense. Despite their defensive efforts the Germans made steady progress and finally the British were forced to withdraw from much of the territory that they had captured during the offensive.
The British had 47,596 casualties during the battle of which 9,000 were taken prisoner and the German suffered 53,300 casualties of which 11,105 were prisoners.