Born in 1887, Dalton was educated at Eton and King's College, Cambridge (where he read mathematics and economics, taught by Pigou and Keynes). He discovered Fabian Socialism together with his close friend, Rupert Brooke. Dalton became a lifelong member of the Fabian Society (1919-1962) and attended the London School of Economics at the Webbs’ instigation to get his doctorate in economics. His diary was inspired by the example of Beatrice Webb and began during the First World War, when he was serving with the Royal Artillery in Italy.
This diary is so valuable because it is the only diary of a prominent Labour politician kept for much of the period, because of the amount of detail recorded, and because of the clear picture it provides of all the manoeuvres and finagling in party politics and government which escape public notice. Contained within 56 notebooks and folders, it amounts to roughly 1.5 million words.