Aleister Crowley, born Edward Alexander Crowley (12 October 1875 - 1 December 1947) was an occultist, mystic, sexual revolutionary, and drug addict (especially heroin).

Other interests and accomplishments were wide-ranging (he was a chess master, mountain climber, poet, writer, painter, astrologer and social critic). He was quite notorious during his life, and was dubbed "The Wickedest Man In the World"; the term first appeared in 1928 in John Bull, a tabloid pictorial of the day.