During the filming of this movie, Sam Peckinpah was so obnoxious and abusive towards his actors that Charlton Heston physically threatened the director with a sabre. Heston later remarked that this was the only time he had ever threatened anybody on a movie set.
Lee Marvin was Sam Peckinpah's initial choice for the role of Samuel Potts, but Marvin wanted too much money. Marvin's agent suggested 'James Coburn' for the part, and Coburn ultimately got the role.
Woody Strode was considered for the part that went to Brock Peters. Strode was part Native American and he wrote in his memoirs that he didn't get the part because he was told by Sam Peckinpah that he looked too much "like a half-breed" to play the part.
Shooting on the movie was wrapped up early by studio executives, in the interest of controlling costs, before some important scenes were filmed. Charlton Heston offered to return his entire salary for the movie if the studio would agree to film the necessary scenes and re-shoots. The studio kept his paycheck and never allowed any more footage to be shot anyway.
After the success of Sam Peckinpah's later The Wild Bunch (1969), Columbia told him that they would allow him to re-shoot parts of this film that had been cut from the release version. Peckinpah, naturally, declined the offer.
Sam Peckinpah had been pitching a movie about Gen. George Armstrong Custer and the Battle of the Little Big Horn, because he thought it was fascinating how Custer became a glorious, immortal American hero after being defeated in battle and killed. Nothing ever came of it, but Peckinpah thought the story of "Major Dundee" to be similar enough, and took this job instead.
The script was originally written with John Ford in mind to direct, but Ford was busy working on Cheyenne Autumn (1964) and in any case was uninterested.
Average Shot Length (ASL) = 4.7 seconds
The role of Capt. Tyreen was intended for Anthony Quinn, who pulled out.
Sam Peckinpah originally wanted Lucien Ballard, with whom he had had a good working relationship on Ride the High Country (1962), as the director of photography, but producer Jerry Bresler refused the request, making him work with Sam Leavitt, whose credits included Diamond Head (1963), a previous Bresler production, and Cape Fear (1962). Although Leavitt did get along fairly well with Peckinpah, this was the first sign of tension between the director and the producer.
Despite his quarrel with Sam Peckinpah, producer Jerry Bresler fought very hard with Columbia to keep the 136-minute cut (the "Extended Edition" now on DVD) despite its poor reception at its preview, but was rebuffed by the studio.
L.Q. Jones narrates the trailer for the re-release of the extended version.