Thomas Karlsson (born 1972) is a Swedish occultist and esoteric author, with a PhD in the History of Religions from the Stockholm University. In 2007, he held the first Swedish university course in Western Esotericism.
In 1989, he and six other magicians founded Dragon Rouge, a Left-Hand Path initiatory organisation and a Draconian Tradition Order, led by Karlsson. As a book author, he concentrates on occult, philosophy, and paranormal topics. The Dragon Rouge website cites Carlos Castaneda, Julius Evola, and Kenneth Grant as some of the magical writers whose work is read by the order, as are texts by classical philosophers such as Herakleitos, Plato, and Plotinos, as well as modern philosophers like Friedrich Nietzsche, Martin Heidegger, and Henri Bergson. Karlsson is also associated with metal bands Therion and Shadowseeds. His personal influences include Sumerian mythology, alchemy, tantra, the Goetia, and the Qliphoth. In an interview dated in 2003, he claims he experienced astral projections as a child, but did not think of them as supernatural experiences until he started formally exploring the occult.