Originally, Truman Capote was the screenwriter, and his draft included making Nick a homosexual and Jordan Baker a vindictive lesbian. Capote was fired, and Francis Ford Coppola finished his draft in three weeks.
The rights for the novel were purchased by producer Robert Evans in 1971 so that his wife at the time, Ali MacGraw, could play the part of Daisy. A shooting script wasn't ready yet, and MacGraw agreed to star in The Getaway as filler. During the production of The Getaway MacGraw fell in love with co-star Steve McQueen and left Evans for him. Mia Farrow was then picked to play Daisy.
Mia Farrow was pregnant during filming and the director filmed around that by including close up shots of Farrow, and having her wear a lot of flowing costumes.
Many of the male extras in the party scenes were recruited from the Naval War College in Newport, Rhode Island because military officers already wore the clean-cut hairstyles that were worn by men in the period of the film.
According to Robert Evans in his memoirs Warren Beatty was approached to play Gatsby but wanted to direct the film and suggested Evans play the role himself. Jack Nicholson was offered but rejected the role because he didn't believe Ali MacGraw to be appropriate casting for Daisy (she was later replaced with Mia Farrow) and Steve McQueen was also considered and rejected for the role.
Natalie Wood was offered the role of Daisy, but she allegedly became furious when the producers insisted on a screen test since the actress hadn't been in a movie for over 5 years. She balked and negotiations ended.
Mia Farrow writes that the main reason she was unable to create on-screen chemistry with co-star Robert Redford was because of Redford's total absorption in the Watergate scandals that were rocking Washington, D.C. at the time of filming. Farrow says Redford spent all his free time locked in his trailer, watching the political scandal unfold on television. Two years after making this movie, Redford played Watergate reporter Bob Woodward in All the President's Men.