How Green Was My Valley is a 1941 American drama film directed by John Ford, adapted by Philip Dunne from the 1939 novel of the same title by Richard Llewellyn. It stars Walter Pidgeon, Maureen O'Hara, Anna Lee, Donald Crisp, and a young Roddy McDowall.

Philip Ives Dunne was an American screenwriter, film director and producer, who worked prolifically from 1932 until 1965. He spent the majority of his career at 20th Century Fox. He crafted well regarded romantic and historical dramas, usually adapted from another medium. Dunne was a leading Screen Writers Guild organizer and was politically active during the "Hollywood Blacklist" episode of the 1940s–1950s. He is best known for the films How Green Was My Valley (1941), The Ghost and Mrs. Muir (1947), The Robe (1953) and The Agony and the Ecstasy (1965).