Percy Bysshe Shelley (August 4, 1792-July 8, 1822) was one of the greatest British Romantic and lyric poets. His influence ranged from literature to political and social theory. Karl Marx and Leo Tolstoy were influenced Shelley's theories of morality, economics, and nonviolent resistance. Shelley is best known for his classic poems, "Ode to the West Wind"; "The Cloud"; and "Adonais." His verse dramas include The Cenci (1819) and Prometheus Unbound (1820). His second wife, Mary Shelley, was the author of Frankenstein.