Eugene O’Neill’s drama is generally approached from heterogeneous perspectives: if there is a critical consensus concerning O’Neill’s canonical position in American theater, it is probably due to the critics’ tendency to neglect the early plays. This dissertation aims to reconstruct the link between the plays and the shifting contexts in which they were elaborated in order to highlight O’Neill’s aesthetics of contradiction fueled by an unsatisfied quest for belonging. Instead of positing that O’Neill’s achievement lies in the late plays, this study aims at evaluating the early plays, as they constitute the matrix of his writing. The quest for belonging runs through O’Neill’s plays, which also show a constant tension between avant-garde and commercial stage, individual and collective behavior. O’Neill’s plays are difficult to apprehend, as they are extremely heterogeneous. But as a whole, they appear directed, however, toward one single pursuit: the quest for belonging which characterizes the context of production as much as the writing. By considering the plays as a whole, unified by the impossible quest for a community, one may attempt a new approach to O’Neill’s works, as the contradictions inherent in the writing show how O’Neill’s body of work produces its own ambiguity and interest