John Wayne was the original choice for Reisman in 1966, but he turned down the role because he objected to the adultery present in the original script, which featured the character having a relationship with an Englishwoman whose husband was fighting on the Continent. He went on to star in The Green Berets and was replaced by Lee Marvin. Jack Palance refused the "Archer Maggott" role when they would not rewrite the script to make his character lose his racism; Telly Savalas took the role, instead.

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