Aleister Crowley, born Edward Alexander Crowley, and also known as both Frater Perdurabo and The Great Beast 666, was an English occultist, mystic, ceremonial magician, poet and mountaineer, who was responsible for founding the religious philosophy of Thelema. In his role as the founder of the Thelemite philosophy, he came to see himself as the prophet who was entrusted with informing humanity that it was entering the new Aeon of Horus in the early 20th century.
Born into a wealthy upper-class family, as a young man he became a member of the esoteric Hermetic Order of the Golden Dawn. Subsequently he claimed that he was contacted by his Holy Guardian Angel, an entity he named Aiwass, while staying in Egypt in 1904, and that he ‘received’ a text known as The Book of the Law from what he claimed was a divine source, and around which he would come to develop his new philosophy of Thelema. He would go on to found his own occult society, the A∴A∴ and eventually rose to become a leader of Ordo Templi Orientis (O.T.O.), before founding a religious commune in Cefalù known as the Abbey of Thelema, which he led from 1920 until 1923. After abandoning the Abbey amid widespread opposition, Crowley returned to Britain, where he continued to promote Thelema until his death.
Crowley was also bisexual, a recreational drug experimenter and a social critic. In many of these roles he “was in revolt against the moral and religious values of his time”, espousing a form of libertinism based upon the rule of “Do What Thou Wilt”. Because of this, he gained widespread notoriety during his lifetime, and was denounced in the popular press of the day as “the wickedest man in the world”.
Crowley has remained an influential figure and is widely thought of as the most influential occultist of all time. In 2002, a BBC poll described him as being the seventy-third greatest Briton of all time. References to him can be found in the works of numerous writers, musicians and filmmakers, and he has also been cited as a key influence on many later esoteric groups and individuals, including Ron L. Hubbard, Kenneth Grant, Kenneth Anger, Jack Parsons, Gerald Gardner, Robert Anton Wilson and, to some degree, Austin Osman Spare.