What this thesis attempts to do is to render as full a picture as possible of Yeats's interest in Ben Jonson, using to the fullest advantage the many hints that come from Yeats and secondary oriticism. Specifically, the focus of this paper is on the process by which Yeats was able, like Eliot, Pound and others, to found a tough, new poetic style with reference to this seventeenth-century period of Jonson. Yeats's reading of "Jonson and the others," which took place at the turn of this century, triggered a whole series of discoveries by Yeats which anticipated the aesthetic beliefs of his famous friends in the modern movement, whose later influence upon his poetry generally fortified poetic principles which had already found their way into his work. His early plays for the Abbey Theatre, for instance, demonstrate his call for a return to the "roots" of poet ic power that Synge associated with the best plays of Jonson and Moliere, and his poetry of that period demonstrates his first attempt at finding the "passionate syntax" of Jonson, Donne, Shakespeare and others.