Had Yeats stopped writing before middle age, he may only have been remembered as a minor literary figure; his greatest work was produced between the ages of 50 and 75, an accomplishment that remains unique in the history of poetry. He attained a perfection of form in his proud, strong verse that was unrivaled, winning the Nobel Prize for literature in 1923. He is still revered as not only a great Irish poet, but as one of the greatest poets of the 20th century."