Recently re-watched this favorite. All of Sergio Leone's westerns are superb cinematic experiences and Once Upon A Time In The West (1968) is no exception.
The screenplay was written by Sergio Leone and Sergio Donati (a prolific and still active screenwriter; his other writing credits include The Big Gundown (1966), Duck, You Sucker aka A Fistful of Dynamite (1971) and Cry, Onion! aka Spaghetti Western from 1976) and story credit was given to Dario Argento, Bernardo Bertolucci and Sergio Leone.
A great deal of talent was also displayed on the screen. Henry Fonda played against his good guy screen image as the very nasty Frank. Claudia Cardinale, Jason Robards, Charles Bronson, Woody Strode, Keenan Wynn and the always appreciated Jack Elam also bring top notch performances and textured characterizations to the film. Rumor has it that Sergio Leone had initially intended for Clint Eastwood, Lee Van Cleef and Eli Wallach to reunite and play the three gunman at the film's begining; but scheduling all three actors for the shooting proved to be too difficult and the idea was abandoned.
clip from BBC documentary
SOMETHING TO DO WITH DEATH
SERGIO LEONE'S "ONCE UPON A TIME IN THE WEST"
with film historian and author Christopher Frayling
Henry Fonda Talks about his casting in Once Upon A Time in the West