Wag the Director: The wrestling match originally took place by a meadow at night. Oliver Reed disliked this idea and suggested it take place indoors. He got his point across by performing a wrestling move on Ken Russell.
Producer Larry Kramer wanted Edward Fox for the role of Gerald. Fox fitted Lawrence's description of the character ("blond, glacial and Nordic"), but United Artists, the studio financing the production, imposed Oliver Reed, a more bankable star, as Gerald even though he was not physically like Lawrence's description of the character. Michael Caine was offered the role, but couldn't handle the nudity.
Faye Dunaway and Vanessa Redgrave turned down the role of Ursula, finding it the less interesting of the two sisters and that they'd be overshadowed by Glenda Jackson. Shirley MacLaine was set to play the role, but backed out due to the nude scenes.