All of the witnesses as portrayed in the film are the actual witnesses who testified at Wirz's trial, and their dialogue in many cases is taken almost verbatim from the trial transcript. The major change from history is that Wirz did not testify and the whole "moral issue", around which this film revolves, was never raised at the trial.
Richard Basehart portrayed Henry Wirz with a relatively light Germanic accent, while in real life, and at the actual trial, Wirz was known to have a heavy, or thick, Germanic accent. This was done to make the character's dialogue clear and intelligible for television audiences.
Lou Frizzell, who plays Jasper Culver in this production of "The Andersonville Trial", played a Union Soldier in the original 1959 Broadway stage production. He is the only one of the original Broadway cast to appear in this production. He played a non-speaking role as a Union soldier and understudied the role of Jasper Culver, which he plays here. Harry Townes, who plays Col. Chandler in this version, was Otis Baker in the original version as a CBS' "Climax."
The Broadway production of "The Andersonville Trial" by Saul Levitt opened at the Henry Miller's Theater in New York on December 29, 1959 and ran for 179 performances.