British political scientist and historian specializing in modern Russian history.

He joined the Foreign Office in 1916 and was assistant editor of The Times during 1941–46. He was subsequently tutor and fellow of Balliol College, Oxford, and a fellow of Trinity College, Cambridge. His best known works include the biography Michael Bakunin (1937) and the multivolume, four-part series A History of Soviet Russia, which includes The Bolshevik Revolution 1917–23 (vol. 1, 1950; vol. 2, 1952; vol. 3, 1953), The Interregnum 1923–24 (vol. 4, 1954), Socialism in One Country 1924–26 (vol. 5, 1958; vol. 6, 1959; vol. 7, 1964), and The Foundations of a Planned Economy, 1926–29 (vol. 8, with R.W. Davies, 1969, vol. 9, 1971, vol. 10, 1976–78). He also wrote The New Society (1951), What Is History? (1961), 1917: Before and After (1968), and From Napoleon to Stalin (essays, 1980).