S. L. MacGregor Mathers (18541918) was a prominent scholar and leader of the occult movement in Britian at the turn of the century. A lifelong fascination with mysticism and Celtic symbolism led Mathers to hold high office in the Rosicrucian Society of England, and eventually to become a founder of the Hermetic Order of the Golden Dawn. He is also well known for having been a key tutor to Aleister Crowley.