[5] During World War II, on a trans-Atlantic crossing, Acorn suffered a wound from depth charges.
He returned to Prince Edward Island and moved to Montreal, Quebec in 1956 and was for a time a member of the Labor-Progressive Party.
[15][16] In 1977, Acorn introduced the Jackpine sonnet, a form designed to be as irregular and spikey (and Canadian) as a jack pine tree, but with internal structure and integrity.
Acorn died in his home town of Charlottetown on August 20, 1986, due to complications associated with his heart condition and diabetes.
According to fellow poet and friend Jim Deahl, he had "lost his will to live after the death of a younger sister.