Walt Whitman is oe of America's most celebrated poets, and he was famous among his contemporaries in the mid-19th century, but that wasn't necessarily a good thing. The essayist and journalist made waves with his anthology Leaves of Grass, a collection of poetry that bridged the gaps between Transcendentalism and Realism but was considered obscene by much of the general public at the time. Nevertheless, his influential collection subsequently made him one of the greatest inspirations of generations of poets and writers, and it helped establish him as the "father of free verse."