Walt Whitman, the defining 19th-century poetic voice of America, inspired several generations of European composers. In the 20th century, Whitman’s poetry was adapted during World War I by Othmar Schoeck. The catastrophe of World War II inspired Kurt Weill to turn to Whitman’s writings. Franz Schreker and Ralph Vaughan Williams were drawn to Whitman’s most famous collection, Leaves of Grass, seeking to create music worthy of the power of Whitman’s poetry.