Laurence Olivier in the titular Godfather role instead of Marlon Brando?
Dustin Hoffman or Martin Sheen as Michael Corleone instead of Al Pacino?
Ben Gazzara or John Saxon as Sonny instead of James Caan? ("Jimmy," per Coppola's notes.)
On the heels of news that Coppola is working on a new cinematic project about a multi-generational Italian-American family, the blog Dangerous Minds has collected a few of the names associated with The Godfather that might have been: Ernest Borgnine and Danny Thomas as Vito Corleone, Robert Redford and Jack Nicholson as Michael (per this 2009 Vanity Fair piece), Paul Newman and Steve McQueen for the part of Tom, and Mia Farrow as Kay (per Oscars.org).
Apparently the studio and the director had differing views about quite a few actors. Pacino, in particular, was not high on Paramount's list – but Coppola eventually wore them down.
It's worth pointing out that the movie could have been released with a different director at the helm, too. As Coppola explained in a 1994 interview, "The Godfather was a very unappreciated movie when we were making it. They were very unhappy with it. They didn't like the cast. They didn't like the way I was shooting it. I was always on the verge of getting fired."
In the immortal words of Michael Corleone, "It's not personal ... It's strictly business."
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