Because the movie was filmed in Thailand some viewers erroneously believe the story is based there.The story is set in Vietnam or French Indochina as it was then called.
Producer Dino De Laurentiis had wanted Sir Peter Ustinov for the role of Albert, but Ustinov was unavailable.
At the time of production it was reported that the film would be shot in Ceylon (Sri Lanka) and Saigon.Ultimately, all of the film's exteriors were filmed in Petchburi and Bangkok, Thailand.It was impossible to film in Vietnam due to the Indochina War raging on.