According to Steven Bach's 'Final Cut', Clint Eastwood was disappointed with the film's initial disappointing nine million dollar receipts, and blamed United Artists for inadequately promoting the film. Despite his relationship with the studio on the spaghetti Westerns and a two-picture deal from the studio, he never made another film for them.
Because five year-old Kyle Eastwood said one word of dialogue, which was "Hi!", this action classified him, in terms of the actor's guild rules, as being in the dialogue category, and as such, had to be paid scale, which was at the time, 128 dollars.
Jeff Bridges was nominated for a Best Supporting Actor Academy Award, his second Oscar nomination, and his last until Starman (1984). According to the book "Clint: The Life and Legend" (1999) by Patrick McGilligan, Clint Eastwood believed that his own performance was worthy of an Oscar nomination.
Jeff Bridges is seen wearing drag in this movie. Bridges once said of this: "It's mind blowing! When you glance in a mirror, you feel like you're looking at your sister!". Jeff got a bit of flak and wisecracks about his role as a leading lady from both actors and stars, brother and father, Beau Bridges and Lloyd Bridges.
The dangerous stunt where Clint Eastwood leaps onto a speeding car being driven by Jeff Bridges and hooks his leg inside the car window whilst holding onto the door handle was performed by Eastwood himself.
According to Final Cut: The Making and Unmaking of Heaven's Gate (2004), Clint Eastwood did not like to do more than three takes for a shot. Jeff Bridges said, "I would always go to Mike [Michael Cimino] and say 'I think I can do one more. I got an idea.' And Mike would say 'I gotta ask Clint.' Clint would say, 'Give the kid a shot.'" Moreover, First assistant director Charles Okun added, "Clint was the only guy that ever said 'No'. Michael said 'OK, let's go for another take. 'If it was take four, Clint would say 'No we got enough. We got it.'...And if [Cimino] took too long to get it ready, [Eastwood] would say, 'It's good, let's go.'"
The church used in the opening scenes was the St. John's Lutheran Church in Hobson, Montana. The church was sold in 1980 and dismantled, with plans to move it across the state to Troy, Montana. Eventually these plans were scrapped along with the church itself.
On January 8th 1973, Boxoffice magazine announced that the Malpaso Company and United Artists had "concluded an agreement for the release and production of two films starring Clint Eastwood - " Thunderbolt " and " Lightfoot "!
Whilst shooting in Montana, a visiting Utah theater exhibitor said to Clint Eastwood that showing moving pictures was just a part-time hobby for him, and that his real business was raising turkeys, whereupon Eastwood replied, "My business is seeing to it that I don't!".
Michael Cimino modeled 'Thunderbolt and Lightfoot (1974)' after one of his favorite films from the 1950s, Captain Lightfoot (1955), directed by Douglas Sirk. That film follows the adventures of two Irish highwaymen (Captain Thunderbolt and Captain Lightfoot) as they attempt to raise money to support their Irish revolutionary society.