X, Essayist; Eustace Budgell (St. Thomas, Exeter, England 19 August 1686 - 4 May 1737).

Doctor X, Writer; Alan Edward Nourse (Des Moines, Iowa 11 August 1928 - 19 July 1992).

Ex-Private X, Writer; Alfred McLelland Burrage (England 1 July 1889 - 18 December 1956).

Malcolm X, Civil rights campaigner; Malcolm Little (Omaha, Nebraska 19 May 1925 - 21 February 1965). Assassinated.

Michael X, Civil rights activist; Michael Abdul Malik ne Michael de Freitas (Trinidad 1933 - 1975).

Xariffa: Mary Ashley Townsend, nee Mary Ashley Van Voorhis (Lyons, New York 1832-1901).

Deng Xiaoping, Political leader; Deng Xixian (Paifang, Sichuan, China 22 August 1904).

X-Pac, Professional wrestler; Sean Waltman (Minneapolis, Minnesota 13 July 1972 in ). Uses other pseudonyms in the ring, including The 1-2-3 Kid, Syxx, and Syxx-Pac.

Xuxa, Singer and television host; Maria da Graça Meneghel (Santa Rosa, Brazil 27 March 1963).