Donald was born in Sain John, New Brunswick, Canada to Dorothy McNichol and Frederick Sutherland, with Scottish roots on his mother's side. He grew up in Bridgewater, Nova Scotia. His mother was a mathematics teacher, and his father was head of the local bus, gas and electric company. As a child he suffered from polio, hepatitis and rheumatic fever.
He studied at Victoria College, University of Toronto where he graduated in Engineering and Drama. They then went to London to study at the Academy of Music and Dramatic Art.
At first he worked in the UK, on TV and Film, working with Christopher Lee, and venturing into the war film genre. A gradual build up in his career resulted in his ultimate great success and reputation as a Hollywood Great.
Donald's first wife was Lois Hardwick, and they were married for 7 years (1959-1966). He had twins with his second wife, Shirley Douglas (1966-1970) (Kiefer and Rachel), and three sons with his current wife, Francine Racette (Rossif, Angus and Roeg), whom he has been married to since 1972. Shirley's father was Tommy Douglas, acclaimed Member of the Canadian House of Commons.
As of 2008, Donald has a home in Georgeville, Quebec.