Robert Bruce Montgomery (1921-1978) was born at Chesham Bois, Buckinghamshire, on 2 October 1921, the third child in the family of three daughters and one son of Robert Ernest Montgomery (1878-1962) and his wife, Marion Blackwood Jarvie (d 1971). Educated at Merchant Taylors' School, where the club-foot for which he was operated on several times in childhood prevented his participation in sport, he was a gifted student and already a talented composer by the time he went to St John's College, Oxford in 1940. For three years he read Modern Languages under W.G. Moore (his tutorial partner was the poet Alan Ross) and was College organist. Expected by his contemporaries to get a First, he spent the Easter vacation before his Final Examinations writing a detective novel and gained only 'an ignominious Second', as he recalled in later life. However, The Case of the Gilded Fly, written under the pseudonym Edmund Crispin and featuring as its hero Oxford Professor of English, Gervase Fen, was published in 1944 and was an immediate success. It was the first of eight Gervase Fen novels published in Britain and America between 1944 and 1951, the most productive period of Montgomery's life when he was writing and composing fluently and with pleasure.

As a composer, Montgomery contributed to most genres. His Oxford Requiem was commissioned by the Oxford Bach Choir in 1951 and is probably his best-known concert work. His operas include John Barleycorn, a ballad opera for children. However, Montgomery is chiefly known for his film scores, of which he wrote over thiry between 1949 and 1966. His scores for several of the enormously popular 'Carry on' and 'Doctor' film series probably reached the widest audiences. He died from alcohol-related problems at the age of 56.