Douglas Haig was born in Edinburgh. He was educated at Clifton School, Bristol, and Oxford University. He entered the army in 1885, serving as a cavalry officer in the Sudan and distinguishing himself in South Africa during the Boer War (1899-1902). He served under Lord Kitchener in India. From 1905 to 1909 he played an important role in reforming the British Army.

At the outbreak of the First World War in 1914 Haig served as Commander of the First Army Corps of the British Expeditionary Force, and shortly after, in 1915, was promoted to Commander in Chief of the British Expeditionary Force, replacing Sir John French.

Haig was instrumental in pursuing some of the great battles of attrition during the War, notably those of the Somme in 1916 and Passchendaele in 1917. These incurred a huge loss to the army both in the number of killed and wounded (60,000 on the first day of the Somme alone).

Greatly admired among his fellow officers, Haig was almost equally mistrusted by the Prime Minister, Lloyd George. He considered Haig to be wasting soldiers' lives without any prospect of victory. By March 1918, during 'Operation Michael', the major German offensive when the allies were forced back to within forty miles of Paris, things looked particularly bleak for the allied command. Haig argued that the French leader, General Foch, should assume supreme control of the allied forces during the crisis and by September of that year the tables had been turned on the Germans. An armistice brought the War to a close on 11 November 1918.

The part played by Haig in the events of the War has always been a subject of controversy. The opposing schools of thought seem irreconcilable. Some see Haig as the 'saviour of the nation' who brought about the defeat of the German army by a war of attrition on the Western Front. Others view him as an incompetent butcher, unable to cope with the changing nature of warfare and leading untold thousands of young men to certain death for the price of a few yards of ground.