@Merry Andrew,
According to the film historians in the "Special Features" section of the DVD (it's for
Captain Blood, the granddaddy of all Hollywood swashbucklers), he was brought over from England by one of the Warner Brothers (not Jack, although he took over production of the film). He had had some modest roles in England, including a lead in a murder mystery. That manslaughter story sounds like BS to me.
It was his debut in an American film, and he had the lead role. Warner Brothers had had some serious flops, so they weren't putting up big money on that one. The female lead was Olivia de Havilland, and that was her first leading role. Apparently, she had signed up with Warner for a seven year contract, and was beginning to regret it. Basil Rathbone was one of the heavies (great casting), and according to the film history boys, was
the swashbuckler of Hollywood, being fanatical about fencing. It was directed by Michael Curtiz (
I'm a Yankee Doodle Dandy,
Casablanca) with the musical score by Erich Korngold. Quite a line-up, and in 1935, Warner used all those folks to try to save money on the production. Curtiz drove Jack Warner nuts with his "spare no expense" attitude.