Montgomery Clift only agreed to do this movie so that he could later do Reflections in a Golden Eye (1967). Following his death, the role went to Marlon Brando.
Clift insisted on doing all of the stunts in this film himself, which he did despite poor health.
At the end of the movie, the monument inscribed "zum gedenken an die opfer der kriege" means "to commemorate the victims of war".