Also according to Turner Classic Movies, Marlon Brando insisted on playing Ace Gruver with a Southern accent, against the will of the director and producers. Brando adopted a nondescript Southern accent for Gruver, despite the objections of director Joshua Logan, who didn't think that a general's son who was West Point-educated would speak that way.
Audrey Hepburn was offered the role of a Japanese bride opposite Marlon Brando but turned it down. She explained that she "couldn't possibly play an Oriental. No one would believe me; they'd laugh. It's a lovely script, however I know what I can and can't do. And if you did persuade me, you would regret it, because I would be terrible."
In 1956, more than 10,000 American servicemen had defied regulations and married Japanese women, as indeed had the novel's author, James Michener.