Hugh Dalton was one of the most effective and strangest of modern political leaders. Born the son of a tutor to royal princes, Dalton was educated at Eton and King's College, Cambridge, where he was taught by Maynard Keynes, fell under the spell of Rupert Brooke, and learned about socialism from Keir Hardie and Beatrice Webb. He entered Parliament in 1924, and for three decades his impact on government policy and on the leadership, organization and philosophy of the Labour party was immense. In this biography, Pimlott makes use of official records, interviews, private papers and the hitherto unpublished Dalton diaries.