William Alexander Percy (May 14, 1885 – January 21, 1942), was a lawyer, planter, and poet from Greenville, Mississippi. His autobiography Lanterns on the Levee (Knopf 1941) became a bestseller. His father LeRoy Percy was the last United States Senator from Mississippi elected by the legislature. In a largely Protestant state, the younger Percy championed the Roman Catholicism of his French mother.
He was born to Camille, a French Catholic, and LeRoy Percy, of the planter class in Mississippi, and grew up in Greenville on the big river. His father was elected as US senator in 1910. As an attorney and planter with 20,000 acres under cultivation for cotton, he was very influential at the Episcopal university, Sewanee: The University of the South in Sewanee, Tennessee, a postbellum tradition in his family. He spent a year in Paris before going to Harvard for a law degree. After returning to Greenville, Percy joined his father's firm in the practice of law.
During World War I, Percy joined the Commission for Relief in Belgium in November 1916. He served in Belgium as a delegate until the withdrawal of American personnel upon the U.S. declaration of war in April 1917. He served in the US Army in World War I, earning the rank of Captain and the Croix de Guerre.
From 1925 to 1932, Percy edited the Yale Younger Poets series, the first of its kind in the country. He also published four volumes of poetry with the Yale University Press. A Southern man of letters, Percy befriended many fellow writers, Southern, Northern and European, including William Faulkner. He socialized with Langston Hughes and other people in and about the Harlem Renaissance. Percy was a sort of godfather to the Fugitives at Vanderbilt, or Southern Agrarians, as John Crowe Ransom, Allen Tate and Robert Penn Warren were often called.