Éliphas Lévi, (the pen name of Abbé Louis Constant, b. 1810, d. 1875), was one of the leading occultists of the 19th century. For most of his life he was a Roman Catholic priest; even after he was defrocked in 1844, his views continued to have a strong Catholic influence. His books, which were not translated into English until after his death, influenced the development of other occultists such as Albert Pike, Helena Blavatsky, A.E. Waite, and Aleister Crowley.