William Butler Yeats was an Irish poet and one of the foremost figures of 20th-century literature. A pillar of both the Irish and British literary establishments, his earliest volume of verse was published in 1889, and its slow-paced and lyrical poems display Yeats's debts to Edmund Spenser, Percy Bysshe Shelley, and the poets of the Pre-Raphaelite Brotherhood. From 1900, Yeats's poetry grew more physical and realistic. In 1923, he was awarded the Nobel Prize in Literature. (Wikipedia )