Leaves of Grass, collection of poetry by American author Walt Whitman, first presented as a group of 12 poems published anonymously in 1855. The poems of Leaves of Grass are loosely connected, with each representing Whitman’s celebration of his philosophy of life and humanity. This book is notable for its discussion of delight in sensual pleasure during a tie when such candid displays were considered immoral. It was highly controversial during its time for its explicit sexual imagery, especially in the first edition. Where much previous poetry, especially English, relied on symbolism, allegory, and meditation on the religious and spiritual, it exalted the body and the material world. Influenced by Ralph Waldo Emerson and the Transcendentalist movement, itself offshoot of Romanticism.