Ellen Churchill Semple (January 8, 1863 – May 8, 1932) was an American geographer. Ellen was born in Louisville, Kentucky, the youngest of five children by Alexander Bonner Semple and Emerine Price. She is most closely associated with work in anthropogeography and environmentalism. In a series of books and papers she communicated certain aspects of the work of German geographer Friedrich Ratzel to the Anglophone community. Standard disciplinary accounts often attribute to Semple a prevailing interest in environmental determinism, a theory that the physical environment, rather than social conditions, determines culture; however her later work emphasized environmental influences as opposed to the environment's deterministic effect on culture, reflecting broader academic discontent with environmental determinism after the First World War. Semple studied at Vassar College and the University of Leipzig. She taught at the University of Chicago and at Clark University. She died at West Palm Beach, Florida. Ellen C. Semple Elementary School in Louisville is named after Semple. She is buried in the Cave Hill National Cemetery in Louisville.