Jefferson, Mark (Sylvester William) (1863–1949)

US geographer. He was in charge of geography at Ypsilanti's Normal College (now Eastern Michian University) 1901–39. A skilled linguist, enthusiastic fieldworker, and prolific writer, he published numerous articles and books; among his better known works are Men in Europe 1924, Principles of Geography 1926, and Man in the United States 1933.

He was born in Melrose, Massachusetts. He studied at Boston University, then worked at the National Observatory in Cordoba, Argentina, in 1883, before returning to Boston and graduating in 1889. He then taught in Massachusetts public schools, and was superintendent of schools in Lexington 1893–96. He earned his MA from Harvard in 1898.