The Battle of Cambrai was a British attack in the First World War, followed by the biggest German counter-attack against the British Expeditionary Force (BEF) since 1914. The town of Cambrai, in the département of Nord, in France, was an important supply centre for the German Siegfriedstellung and capture of the town and the nearby Bourlon Ridge would threaten the rear of the German line to the north. Major General Henry Tudor, Commander, Royal Artillery (CRA), of the 9th (Scottish) Division, advocated the use of new artillery-infantry tactics on his sector of the front. During preparations, J. F. C. Fuller, a staff officer with the Tank Corps, looked for places to use tanks for raids. General Julian Byng, commander of the Third Army, decided to combine both plans. The French and British armies had used tanks en masse earlier in 1917, although to considerably less effect.

The British Expeditionary Force (BEF) was the six divisions the British Army sent to the Western Front during the First World War. Planning for a British Expeditionary Force began with the 1906–1912 Haldane Reforms of the British Army carried out by the Secretary of State for War Richard Haldane following the Second Boer War (1899–1902).