Lord Hankey (1877-1963) was a British civil servant and the first Cabinet Secretary, a top aide to Prime Minister David Lloyd George and the War Cabinet that directed Britain in World War One. Mostly derived from the author's diaries, which began in March 1915, this study describes how Lord Hankey contributed to the development of the British system of Cabinet Government during the war years. First published in 1961, the two-volume collection is a history of the Supreme Command of the War; the conduct of the war, the development of the Supreme Command from Balfour to Lloyd George, and the emergence of the Cabinet Secretariat from the Secretariat of the War Cabinet. It contains intimate glimpses of the statesmen, sailors and soldiers who guided affairs towards 1918. This is a fascinating first-hand examination of the people who influenced the conduct of the war, and will be of particular value to students interested in its diplomatic history.