Eugène Ionesco was one of the major figures in the Theatre of the Absurd, the French dramatic movement of the 1940s and 50s that emphasized the absurdity of the modern condition as defined by existential thinkers like Jean-Paul Sartre. The existentialists followed Soren Kierkegaard's dictum that "existence precedes essence"—that is, that man is born into the world without a purpose, and that he must commit himself to a cause for his life to have meaning. Absurdity and purposelessness frames Rhinoceros, which is a study of a single man's transformation, from apathy to responsibility, as the world around him descends into violence and greater levels of absurdity.

Born in Romania in 1912, Ionesco spent his childhood in Paris until his family returned to its homeland. Ionesco quickly developed a hatred for Romania's conservatism and anti-Semitism and, after winning an academic scholarship, returned to France in 1938 to write a thesis. There, he met anti-establishment writers such as Raymond Queneau. He lived in Marseille during World War II. His first play, The Bald Soprano (1950), a one-act piece that borrowed its phrasing from English language-instruction books, garnered little public attention but earned Ionesco respect among the Parisian avant-garde and helped inspire the Theatre of the Absurd.

Spearheaded by Samuel Beckett and other dramatists living in Paris, the Theatre of the Absurd emphasized the absurdity of a world that could not be explained by logic. The Absurdists' other major themes focused on alienation, the specter of death, and the bourgeois mores that, they felt, had displaced the significance of love and humanity in exchange for a diligent work ethic. In the character of Berenger, a semi-autobiographical persona who figures in several of Ionesco's plays, Ionesco portrays the modern man trapped in an office, engaged in shallow relationships, and escaping with alcohol from a world he does not understand. Yet this is all presented in the Theatre of the Absurd's characteristic morbid wit, an often self-conscious, comic sensibility that makes us laugh at the most horrific ideas—death, alienation, evil—in an effort to understand them.

Ionesco wrote a number of plays in the 50s, but it was not until Rhinoceros (first produced in 1960) that he received global attention. He called the play an anti-Nazi work, and it was performed just long enough after World War II for tensions to have settled down, but not so long that the almost visceral fear associated with fascism had dissipated. The debut of Rhinoceros had a reported fifty curtain calls in Germany. This is understandable; the play demonstrates how anyone can fall victim to collective, unconscious thought by allowing their wills to be manipulated by others. Walter Benjamin stated that one could not write poetry after the Holocaust, and though others have since refuted this as hyperbole, the world was indisputably damaged beyond repair and left searching for answers. Ionesco skirted the problem of trying to represent the Holocaust realistically by dressing his play in heavy but apparent symbolism. Through this indirect path, achievable only through the untamed techniques of the Theatre of the Absurd, he comes closer to answering the unanswerable questions left in the wake of fascist brutality.

Ionesco remained a prolific writer until the early 1980s, although none of his works, dramatic or critical, ever reached the same heights of tragedy and comprehension as Rhinoceros. His work has influenced playwrights as diverse as Harold Pinter and Sam Shepard. He died in 1994, but Rhinoceros is still performed across the world as a reminder of the human capacity for evil—when men consciously want to do evil, and, more frighteningly, when they unconsciously desire it.