An American fantasy author, she is best known for her 1983 novel, The Mists of Avalon, and for her popular Darkover series. Her work is often tinged with feminist ideology.
She graduated with a Bachelor of Arts degree from Hardin-Simmons University in Abilene, Texas.
She published her first novel, Falcons of Narabedla, in 1957.
She grew up on a farm in Albany, New York. She married Walter H. Breen in 1964; the couple divorced after Breen was arrested on charges of child sexual abuse.
Her literary work has been compared to that of J.R.R. Tolkien.