The Imperial War Cabinet was created by British Prime Minister David Lloyd George in the spring of 1917 as a means of co-ordinating the British Empire's military policy during the First World War. The body met through 1917 and 1918 and consisted of Lloyd George, Prime Minister of Canada Sir Robert Borden, Prime Minister Louis Botha and Jan Smuts of South Africa, Prime Minister Billy Hughes of Australia, Prime Minister William Massey of New Zealand, the Secretary of State for India, Sir James Meston and other senior ministers from Britain and the dominions.
In 1917 the Imperial War Conference passed a resolution regarding a future special Imperial Conference to readjust the relations of the component parts of the Empire. That readjustment should be based upon the full recognition of the dominions as autonomous nations of an Imperial Commonwealth, with an "adequate voice" in foreign policy.
Winston Churchill revived the Imperial War Cabinet during the Second World War at the insistence of Australian Prime Minister John Curtin. Canadian Prime Minister William Lyon Mackenzie King declined to join the body and as Churchill was already unenthusiastic about sharing power with the dominions, the Imperial War Cabinet's role in the Second World War was greatly diminished in comparison to the previous war.