American theater had made few notable contributions to drama before Eugene O’Neill. The Hairy Ape was O’Neill’s fourth play, and he himself had prepared the public for it in his earlier Anna Christie (pr. 1921) and in his still earlier The Emperor Jones (pr. 1920), in which some of the expressionistic effects he used in The Hairy Ape had been exploited even more fully.
Anna Christie’s protagonist, Mat Burke, is essentially based on a stoker named Driscoll, whom O’Neill had encountered during the time he went to sea, 1910 to 1911. Yank in The Hairy Ape was also suggested by his memories of Driscoll, but as O’Neill progressed in writing the play, Yank increasingly became a highly autobiographical character. Despite his towering intellect and social position, O’Neill, like Yank, felt like an alien caught between two worlds, and much of his best writing grew out of this sense of alienation.