Thomas Bertram Costain (May 8, 1885 - October 8, 1965) was a Canadian journalist who became a best-selling author of historical novels at the age of 57.
In 1942, he realized his long-time dream when his first novel For My Great Folly was published, and it became a best-seller with over 132,000 copies sold. The New York Times reviewer stated at the end of the review "there will be no romantic-adventure lover left unsatisfied." In January 1946 he "retired" to spend the rest of his life writing.
Raised as a Baptist, he was reported in the 1953 Current Biography to be an attendant of the Protestant Episcopal Church. He was described as a handsome, tall, broad-shouldered man with a pink and white complexion, clear blue eyes, and a slight Canadian accent. He was white-haired by the time he began to write novels. He loved animals and could not even kill a bug (but he also loved bridge, and he did not extend the same policy to his partners). He also loved movies and the theatre (he met his future wife when she was performing Ruth in the The Pirates of Penzance).
Costain's work is a mixture of commercial history (such as The White and The Gold, a history of New France to around 1720) and fiction that relies heavily on historic events (one review stated it was hard to tell where history leaves off and apocrypha begins). His most popular novel was The Black Rose (1945). It was a selection of the Literary Guild with a first printing of 650,000 copies and sold over two million copies in its first year.
His research led him to believe that Richard III was a great monarch tarred by conspiracies, after his death, with the murder of the princes in the tower. Costain supported his theories with documentation, suggesting that the real murderer was Henry VII.
Costain died in 1965 at his New York City home of a heart attack at the age of 80. He is buried in Brantford. A public elementary school in Brantford is named in his honour.
His daughter Molly Costain Haycraft became a writer of historical novels.