The Mitchell family was very unhappy with the film, especially the casting of the tall, laconic Gary Cooper in the lead role. The real Billy Mitchell was short with an explosive temper. The family thought James Cagney would have been ideal.
The character played by Charles Bickford, Gen. Jimmy Guthrie, was a fabrication; such a person never existed. Instead, he was used by the filmmakers as a composite representative of two officers: Maj. Gen. Mason M. Patrick (Chief of the Air Service and Mitchell's direct superior at the time of the battleship Ostfriesland's sinking) and Maj. Gen. Robert Lee Howze, who presided over Mitchell's court-martial.
The appearance of Major H. H. ("Hap") Arnold, played by Robert Brubaker in the film, is significant, for it was he who would authorize the famed Doolittle air attack on Tokyo in April 1942. The raid consisted of B-25 Mitchell bombers - named in honor of Billy Mitchell.
Maj. Gen. Charles P. Summerall was the original presiding judge until he was challenged by Mitchell's defense team and subsequently dismissed before testimony commenced. Summerall later gave evidence on the stand as a prosecution witness. Moreover, in interviews with the press, he described Mitchell as "one of that damned kind of soldier who's wonderful in war and terrible in peace."