Gabrielle Maud Vassal, born in March 1880, was a British-born naturalist, born in Rutland, England. In 1901 the family moved to Hampstead in London, where she later met and married Joseph Marguerite Jean-Baptiste Vassal, a physician in the French Colonial Service, in 1903. The newlywed couple then moved to Vietnam in 1904 and later went to French colonies in Africa. Vassal became a keen naturalist and supplied numerous specimens from Vietnam, Gabon and Congo to the Natural History Museum in London for a period of 30 years. She was considered an unusual collector. because she was female, and because she was "operating in French territory and sending specimens to a British museum.” Many of her letters to the museum are still preserved in their archives. Her specimens included several newly discovered species, and a number were named after her, including the yellow-cheeked crested gibbon Nomascus gabriellae. After the outbreak of World War II, the couple returned to France and Gabrielle joined the French Resistance. She helped many downed airmen escape, earning recognition by governments in Britain and the United States. Vassal authored several books, including a novel titled A Romance of the Western Front (1918); On & Off Duty in Annam; In, and Round Yunnan Fou about her time in Vietnam; Life In French Congo (1925 ); and Three Years In Vietnam 1907-1910: Medicine, Chams And Tribesmen In Nhatrang And Surroundings (1910). Vassal later became known as a successful photographer, author and public speaker.