Surprisingly Similar Characters: Juan and Max Lozoya from Don't Turn the Other Cheek, which came out the same year. Both become revolutionary heroes by no will of their own and both had their families killed by soldiers. Also, as mentioned below, Eli Wallach was meant to play one but ended up playing the other.
What Couldhave Been: Eli Wallach was originally meant to play Juan, but United Artists wanted a bigger name, so they got Rod Steiger. Some foreign dubbing companies caught wind of this during the release of 'Don't Turn the Other Cheek' and had the same foreign actors voice both Steiger's Juan and Wallach's Max.