Eldest son of Henry Huxley, served in the British Army from 1914, became battalion bombing officer. Received the Military Cross on the first day of Passchendaele for capturing prisoners whose presence showed the arrival of a fresh German Guards Division. Demobilised in 1919.

Gervas was recruited in 1939 to help set up the wartime Ministry of Information. After the war he sat on the Executive Committee of the British Council, and became a successful author of biographies.[11][12] He died at Chippenham in 1971.

Gervas's second marriage was to Elspeth Grant (1907–1997) in 1931; she had grown up in Kenya and was a friend of Joy Adamson. After the marriage she wrote White man's country: Lord Delamere and the making of Kenya. Her life and work are the subject of a 2002 biography.[14] As an author, Elspeth Huxley was well up to Huxley standards, and one of the few wives who was better-known than her husband. The flame trees of Thika (1959) was perhaps the most celebrated of her thirty books; it was later adapted for television. They had one son, Charles, b.1944.