Celia Buckmaster was born on 28 November 1914, and her youth was spent in London and Buckinghamshire.

In September 1937 she married Robert Gibson-Fleming, but they divorced two years later. Around this time Celia Buckmaster moved in the London literary circles centring on Dylan Thomas, publishing work in progressive literary magazines. She was also close to poet Lynette Roberts, with whom she worked as a professional flower arranger.

In late 1939 Celia Buckmaster travelled to Burma and married Edmund Leach there in February 1940. In 1942, after the Japanese invasion of Burma, Celia returned to England with her new-born baby Loulou, and bought a house in the Hertfordshire village of Holwell. Celia and Edmund later had a son, Alexander, in 1946. The family moved to Cambridge in 1953 where Edmund Leach was a university lecturer. At Holwell Celia wrote her only two published novels, Village Story (1951) and Family Ties (1952).

Edmund Leach was knighted in 1975 and after his retirement the couple lived at Barrington, outside Cambridge. Lady Celia Leach died in 2005.