Richard Romney Sedgwick (29 May 1894 - 20 January 1972) was a British historian, civil servant and diplomat. He was the elder son of Professor Adam Sedgwick, 1854-1913, and Laura Helen Elizabeth Robinson. He married Mana St David Hodson, daughter of Professor T.C.Hodson, in 1936; they had one son and one daughter.
Sedgwick was educated at Weestminster School and Trinity College Cambridge. He became a Fellow of the College in 1919.
His work for The History of Parliament showed that the Whig versus Tory dichotomy survived in the reigns of George I and George II.
Eveline Cruickshanks wrote a book on the Tories and the Jacobite Rising of 1745 and said: "My greatest debt is to the late Romney Sedgwick, a staunch Whig, whose wit and erudition I greatly admired, for a series of discussions, heated at times, but, as I well know, much enjoyed on both sides".