Gilbert Martineau (1918 – 23 August 1995, La Rochelle) was a French naval officer, author of books on Napoleon and his family, honorary consul, and curator of the French properties on St Helena, 1956-1987.
An anglophile, he was living in London when war broke out in 1939, and he joined the Free French in 1940. His wartime service included a period on a British submarine, and service in Mauritania. On demobilization in 1945 he joined the French Naval Reserve, and was called back into the service in 1954-1955. After the war he worked as Director of Publications for Nagel.
In 1956 he decided to take up an appointment on the remote British Island of St Helena as honorary consul and curator of the French properties, a position which he held until 1987. He continued to live at Longwood House for the rest of his life. As well as devoting himself to the restoration of the properties, he was also a prolific author. He died in La Rochelle in 1995.