Anna Sprengel was allegedly an adept of an established mystical organization called the Die Goldene Dammerung. William Wynn Westcott, one of the founding members of the Golden Dawn, said he corresponded with her and received permission to create a new temple, the Isis-Urania Temple No. 3 of the Order of the Golden Dawn in London.
Anna Sprengel is supposed to have already established contact with the person who would become the main leader of the Golden Dawn in Britain, Samuel Liddell MacGregor Mathers (1854-1918). Anna Sprengel give Mathers a charter authorising him to found lodges of the Golden Dawn in Britain. Westcott and Mathers henceforth collaborated to develop the Golden Dawn, notably in France and the United States.