Policitian and author. Born in London, the son of Sir John Gilmour, 2nd Baronet, and educated at Eton and Balliol College, Oxford. After service during World War II, Gilmour was called to the Bar in 1952, but abandoned his legal career just three years later.
Between 1954 and 1966, Gilmour owned The Spectator magazine, and worked as its Editor (1954-59). He went on to serve as Conservative Member of Parliament for Central Norfolk (1962-74) and then Chesham and Amersham (1974-92). He was, in turn, Parliamentary Under-Secretary of State (1970-71), Minister of State (1971-74) and Secretary of State (1974) at the Ministry of Defence under Edward Heath's administration, Chairman of Conservative Research Department (1974-75) and Lord Privy Seal (1979-81) in Margaret Thatcher's government. He was sacked having disagreed fundamentally with the extremes of Thatcherism and became one of her most ardent critics - the so-called "wettest of the wets".
Gilmour succeeded his father to the baronetcy of Craigmillar in 1977. The family connection with Craigmillar Castle goes back to 1660 and, from 1775, they moved to Inch House. His father sold the latter property to the Edinburgh Corporation in 1946. In 1951, in Westminster Abbey, Gilmour married Caroline, daughter of the Walter Montagu Douglas Scott, 8th Duke of Buccleuch (1894 - 1973).
He wrote several books: The Body Politic (1969), Inside Right: a Study of Conservatism (1977), Britain Can Work (1983), Riot, Risings and Revolution (1992), Dancing with Dogma (1992), Whatever Happened to the Tories (1997) and The Making of the Poets: Byron and Shelley in their Time (2002).
Gilmour was raised to the peerage in 1992. He died in Middlesex (England) and was buried in the family plot at Craigmillar Castle. He will be remembered as an intellectual, articulate and well-informed politician.