His Majesty the American (1919)

Synopsis
When Charles Chaplin, Mary Pickford, Douglas Fairbanks and D.W. Griffith formed United Artists, they had a dilemma -- only one of them was contractually free to make a film for the fledgling studio -- and that was Fairbanks. But he came through with this winning picture, playing his usual character (at least for his pre-swashbuckling days) -- a young man with too much energy and vigor for his own good -- in a Prisoner of Zenda-like backdrop. William Brooks (Fairbanks) lives in Manhattan on a mysterious but sizable income. He apparently has no family either. When following the New York Fire Department around begins to pall, he goes to Mexico and tangles with bandits. All this is only preparation for his next adventure -- he is called to a tiny European country where a revolution is going on. It turns out that he is heir to the throne and he manages to squelch the plotters and win the girl (Marjorie Daw) in short order. ~ Janiss Garza, All Movie Guide