The original Hermetic Order of the Golden Dawn was a magical fraternity founded in London in 1888 by Dr. William Wynn Westcott and Samuel Liddell MacGregor Mathers, which ceased to exist under that name in 1903 but which continued under at least two spin-off organizations, the Stella Matutina and the Alpha et Omega, as well as a renamed faction headed by Arthur Edward Waite that underwent further splits.
Influences on Golden Dawn concepts and work include freemasonry, theosophy, Eliphas Levi, Papus and medieval grimoire magic. The synthetization of these influences into a new school of thought is largely the merit of Mathers, who at times was teaching things he had discovered only days or hours before.
The "Golden Dawn," as it is commonly referred to, was probably the single greatest influence on twentieth-century western occultism. While it existed, it was the focal point of the (re-)development of magical thinking in Europe. In it, most concepts of magic and ritual that have since become core elements of Wicca, Thelema, western mystery schools and other forms of magical spirituality were first formulated. Although the influence of chaos magic pursued by the magical order of the Illuminates of Thanateros is arguably challenging the predominance of Golden Dawn magic, the latter remains the spiritual core of nearly all of the more ceremonial branches of western magic.
In its heyday, many cultural celebrities belonged to the Golden Dawn. Some well known members include: