As much as possible, the enactment of the events were made with the original people who survived. Actual maps and documents were used in the film, which was authorized by the U.S. Government. Some footage by the U.S. Signal Corps was also used in the film.
Nearly twenty years after this film, the town of Yaphank, where the army training camp was located, became a focal point for Nazi activity. Camp Siegfried was a summer camp which taught Nazi ideology. It was owned by the German American Bund, an American Nazi organization.