Olivia Hussey was the first choice for the role of Anne, but she turned the role down due to personal problems she was dealing with at the time.
Although "Anne of the Thousand Days" opened on Broadway in 1948, it had to wait until 1969 to be filmed, due to its frank discussions of adultery, illegitimacy, and incest, on which the storyline relies heavily. The old censorship code still existed in the 1940s and 1950s, and would not have allowed a play in which these subjects were discussed to be filmed, no matter how tastefully.
Maxwell Anderson's play "Anne of the thousand days" was originally produced on Broadway at Shubert Theatre. It premiered on 8 December 1948 and closed on 8 October 1949 (288 performances in total).