To help out the war effort, the actors tried hard to keep the number of takes low so as to conserve film. Roughly 30 of the scenes were done in one take.
The original ending was scrapped and a new one shot so that the film would pass the censor. The original ending had both Tyrone Power's and Maureen O'Hara's characters jumping into the sea.
Although it is supposed to be based on Rafael Sabatini's novel "The Black Swan," in fact, the story is completely original, and the only character retained from the original novel is the historical personage Henry Morgan.
The ship in the picture was also used in the films Il grande ammiraglio (1941), Il pirata e la principessa (1944) and Capitan Kidd (1945).
The reissue version was released in black-and-white.