Charles Bronson and Ernest Borgnine decided to go for cigarettes during filming. This meant saddling up in costume, side arms and all, and riding to the nearest town. On the way, the pair was waylaid by a truck full of armed Federales who mistook them for bandits and held them at gunpoint.
One of the first major Hollywood films to be made on location in Mexico. Film-making legislation in Mexico meant that a local director had to be involved in the production in some capacity, though he wasn't actually used.
Eli Wallach has said that the Mexican government was so upset about the negative portrayal of Mexicans in the film that they insisted that the making of The Magnificent Seven (1960) be monitored by censors.
First film released in the "SuperScope" wide screen process. Shot at a conventional 1.37:1 aspect ratio, the film was cropped to 2:1 in post production and then given a CinemaScope compatible (2x) squeeze and blown up to normal frame height. SuperScope was designed to achieve anamorphic prints from standard flat 35mm negatives. The MGM dvd approximates the 2:1 release print aspect ratio. SuperScope was the fore-runner to "Super 35".
For a film made in the mid 1950's, this film has quite fast cutting rate. In 90 minutes of action, the film contains about 1130 edits and other transitions. This equates to an average shot length of just under 5 seconds.
The Mexican authorities were appalled at the way their citizens were depicted in the film so any subsequent Hollywood productions had to conform to some strict rules. This explains why in The Magnificent Seven (1960), the locals are all wearing pristine white clothes.
In her biography "Playing the Field," Mamie Van Doren claimed Burt Lancaster interviewed her for the role of the Countess and attempted to seduce her. She told him she did not wish to get the part in that way and that her mother was waiting for her outside in the car. Lancaster told her she was right and gave her the script to study, and although she officially auditioned, she didn't get the part.