Alfred George Gardyne de Chastelain, DSO, OBE (1906–1974) was a British-Canadian businessman, soldier, and secret agent, noted for his actions during World War II.

On graduation, he moved to Romania and worked for Unirea (a British Petroleum branch) in Bucharest, rising to a managerial position towards the end of the 1930s.

Captured by the Romanian Gendarmerie soon after their landing near Plosca, Teleorman County, he and his team were taken into custody as prisoners of war and held in a Bucharest apartment.

[2] Alongside a group of partners, de Chastelain started "Griffin Enterprises" (1945), a business centered in London and Kent, dealing in film processing, import and exports and other activities.

In 1954, he left that business to accept a post as Vice-President of the Canadian branch of an American oilwell drilling and services company, H. J. Eastman, in Calgary, Alberta.