The Thoth Tarot is a divinatory tarot deck painted by Lady Frieda Harris according to instructions from Aleister Crowley.  Crowley referred to this deck as the “Book of Thoth.” Crowley originally intended the Thoth deck to be a six-month project aimed at updating the traditional pictorial symbolism of the tarot. However, due to increased scope, the project eventually spanned five years, between 1938 and 1943 and both artists died before publication in 1969 by Ordo Templi Orientis. Crowley and Harris painted some of the cards as many as eight times. The illustrations of the deck feature symbolism based upon Crowley’s incorporation of imagery from many disparate disciplines, including science and philosophy and various occult systems (as described in detail in his Book of Thoth).

Crowley himself says about his tarot that it is a reflection of the structure of the universe, and in particular of the solar system as symbolised in the Qabalah (Crowley’s spelling of Kabbalah). By this, he means that the tarot is another way to represent the Kabbalistic Tree of Life with the ten sefirot. The Thoth tarot uses symbols from Egyptian, Greek, Eastern, medieval and Christian traditions but elements are also used from numerology, astrology, alchemy and the Kabbalah. This card deck is more comprehensive than most other card decks and that gives rise to often very different interpretations from different frames of reference.

Aleister Crowley; (born Edward Alexander Crowley; 12 October 1875 – 1 December 1947) was an English occultist, ceremonial magician, poet, painter, novelist, and mountaineer. He founded the religion of Thelema, identifying himself as the prophet entrusted with guiding humanity into the Æon of Horus in the early 20th century. A prolific writer, he published widely over the course of his life.Marguerite Frieda Harris (1877, London, England – 11 May 1962, Srinagar, India) was an artist and, in later life, an associate of the occultist Aleister Crowley. She is best known for her design of Crowley’s Thoth tarot deck.

Source: Wikipedia