S. L. MacGregor Mathers (1854-1918) was a British occultist. He is primarily known as one of the founders of the Hermetic Order of the Golden Dawn, a ceremonial magic order. His books were responsible for making what had been obscure and inaccessible material widely available to the non-academic English speaking world. They have had considerable influence on the development of occult and esoteric thought since their publication, as has his consolidation of the Enochian magical system.