The son of actor and theatre producer Chandler Cowles, he was born in New York City.

[1] In 1966 Cowles played the title role in Edward Albee's short-lived adaptation of James Purdy's comic novel Malcolm on Broadway at the Shubert Theatre.

[2] In 1968, he appeared with Al Pacino and John Cazale in Israel Horovitz's The Indian Wants the Bronx.

In a New York Times profile of his wife, he was described as "the black sheep member of a family with ties to Cowles publishing and Drexel banking".

[5] Cowles was a devout Catholic and taught religious education at the Church of the Nativity in Bethlehem, Connecticut.