Although Gary Cooper was 57, his character Major Thorn was forty years old according to the novel. Early in the film it is mentioned that Thorn's father had recently been killed while still on active service.
Dick York suffered a back injury during filming, and never fully recovered. Continuing back problems forced him to leave Bewitched (1964) in 1969, and effectively ended his career. He spent his last years in poverty.
The film was originally 2 hours 30 minutes, but it was cut down to about two hours. Robert Rossen was restoring the film to its original length when he died in 1966.
After the film was released, both "Variety" and "Films in Review" complained that Gary Cooper was too old for his character.
John Wayne criticized what he perceived to be a "lack of patriotism" of this film because Gary Cooper's character had a task to select five men as candidates for the Congressional Medal of Honor, because Washington needed heroes in a hurry for a World War One recruiting campaign.John Wayne said, "How they got Gary Cooper to do that one! To me, at least, it simply degrades the Medal of Honor. The whole story makes a mockery of America's highest award for valor. The whole premise of the story was wrong, illogical, because they don't pick the type of men the movie picked to win the award, and that can be proved by the very history of the award."