William Slater Brown (November 13, 1896 – June 22, 1997) was an American novelist, biographer, and translator of French literature. Most notably, he was a friend of the poet E. E. Cummings and is best known as the character "B." in Cumming's 1922 memoir/novel The Enormous Room. His books, published under the name Slater Brown, include the novel The Burning Wheel (1943); Ethan Allen and the Green Mountain Boys (1956), a biography for children; and The Heyday of Spiritualism (1970), a study of the 19th-century interest in parapsychology and the occult.