In his 1940 memorial lecture in Dublin, T. S. Eliot pronounced Yeats "one of those few whose history is the history of their own time, who are a part of the consciousness of an age which cannot be understood without them." Modern readers have increasingly agreed, and some now view Yeats even more than Eliot as the greatest modern poet in our language. Son of the painter John Butler Yeats, the poet divided his early years among Dublin, London, and the port of Sligo in western Ireland. Sligo furnished many of the familiar places in his poetry, among them the mountain Ben Bulben and the lake isle of Innisfree. Important influences on his early adulthood included his father, the writer and artist William Morris, the nationalist leader John O'Leary, and the occultist Madame Blavatsky. In 1889 he met the beautiful actress and Irish nationalist Maud Gonne; his long and frustrated love for her (she refused to marry him) would inspire some of his best work. Often and mistakenly viewed as merely a dreamy Celtic twilight, Yeats's work in the 1890s involved a complex attempt to unite his poetic, nationalist, and occult interests in line with his desire to "hammer [his] thoughts into unity." By the turn of the century, Yeats was immersed in the work with the Irish dramatic movement that would culminate in the founding of the Abbey Theatre in 1904 as a national theater for Ireland. Partly as a result of his theatrical experience, his poetry after 1900 began a complex "movement downwards upon life" fully evident in the Responsibilities volume of 1914. After that he published the extraordinary series of great volumes, all written after age 50, that continued until the end of his career. Widely read in various literary and philosophic traditions, Yeats owed his greatest debt to romantic poetry and once described himself, along with his coworkers John Synge and Lady Isabella Augusta Gregory, as a "last romantic." Yet he remained resolutely Irish as well and presented in his verse a persona bearing a subtle, idealized relationship to his everyday self. Political events such as the Easter Rising and the Irish civil war found their way into his poetry, as did personal ones such as marriage to the Englishwoman Georgiana "Georgie" Hyde-Lees in 1917, the birth of his children, and his sometime home in the Norman tower at Ballylee. So, too, did his increasing status as a public man, which included both the Nobel Prize in 1923 and a term as senator of the Irish Free State (1922--28). Yeats's disparate activities led to a lifelong quest for what he called "unity of being," which he pursued by "antinomies," or opposites. These included action and contemplation, life and art, fair and foul, and other famous pairs from his poetry. The most original poet of his age, he was also in ways the most traditional, and certainly the most substantial. His varied literary output included not only poems and plays but an array of prose forms such as essays, philosophy, fiction, reviews, speeches, and editions of folk and literary material. He also frequently revised his own poems, which exist in various published texts helpfully charted in the Variorum edition (1957).
Unlike the directors of the Abbey Theatre, Sean O'Casey was slum-born and bred, self-educated, and deeply involved in the political and labor ferment that preceded Irish independence. His famous group of realistic plays produced at the Abbey form, in effect, a commentary on each stage of the independence movement. The melodramatic The Shadow of a Gunman (1923), the first to be staged, deals with the guerrilla war conducted by the IRA until the peace treaty was signed in 1921. Juno and the Paycock (1925), cast in the mold of classic comedy, describes the civil war and failure of hopes that followed the settlement. The last to be produced, The Plough and the Stars (1926), set off howls of resentment by returning to the Easter 1916 uprising itself, and condemning the vanity of the nationalists and the dogmatism of labor, who squabble while Dublin, in the person of its women, suffers martyrdom. It was expected that the Abbey audience would be unsympathetic. However, when even the Abbey management, in the person of W.B. Yeats, turned against the antiwar play, The Silver Tassie (1928), O'Casey (who had already taken up residence in London and married) determined to remain in "exile." It was an ill-chosen moment to throw himself upon the mercy of a commercial theater, because O'Casey was just embarking on a series of dramatic experiments: Within the Gates (1934), in which the stylized polyphony of urban activities recalls the panorama of The Plough and the Stars and anticipates more modern works such as Arnold Wesker's Kitchen (1959); The Star Turns Red (1940), a vision of an anti-fascist revolution; and Purple Dust (1940), a fantasy cleansing of the remnants of imperialism from Ireland. Without an assured theater, these and his later plays were condemned to productions often amateurish and unhelpful to the reviser, sometimes coming years after O'Casey had reluctantly published the text. (An exception was the exemplary New York production of Within the Gates in 1934. But Irish playwrights have often done better in New York than London.) After World War II, O'Casey turned to a third, still more idiosyncratic form of drama, of which his own favorite example was Cock-A-Doodle-Dandy (1949). Broadly satirical depictions of rural Ireland in the grip of church and complacency, these were Aristophanic comedies with a great deal of folk culture and music hall in their constitution. Their reception was appropriately divided: Cock-A-Doodle-Dandy received its first production at the Royal Court in 1959; The Drums of Father Ned was forced out of the Dublin Festival of 1958. In the 1930s, O'Casey served as a drama critic for London's Time and Tide, producing a group of scathing comments on West End conventionality, which have been published as The Flying Wasp (1937). Other essays on theater appear in The Green Crow (1956), Under a Colored Cap (1963), and Blasts and Benedictions (1967).