One of the great innovative figures in American letters, Walt Whitman created a daring new kind of poetry that became a major force in world literature. His poems have been woven into the very fabric of the American character and have continued to provide inspiration to people and poets for generations. Leaves of Grass, self-published in 1855 and augmented throughout the poet's life, is Whitman's masterpiece. Written in a pure, uninhibited style and combining sensual and mystical sensibilities, it was greeted by Ralph Waldo Emerson as "the most extraordinary piece of wit and wisdom that America has yet contributed." With its bold, joyous voice, its expansive optimism, and its transcendental vision, Leaves of Grass fulfilled Whitman's ambition to create something uniquely American.