A short film i watched in college in 1970. Civil war soldiers hanging enemy soldiers on a bridge.

It might be something like Incident at ox bow creek It may have been in b&w It may have had subtitles. Definitely a short film

Linda: That sounds like La rivière du hibou (1961), or another version of the same story, "An Occurrence at Owl Creek Bridge" by Ambrose Bierce, but I am guessing the 1961 version as that is the most famous version. https://www.imdb.com/title/tt0056300/ Not only did this version win an Oscar for Best Live Action Short Subject, but it was also shown as an episode of "The Twilight Zone".