In 1991, writer Russell McCloud published the popular novel Die Schwarze Sonne von Tashi Lhunpo (German 'The Black Sun of Tashi Lhunpo') which scholar Nicholas Goodrick-Clarke describes as an "occult-Nazi thriller". In the novel, McCloud links the Wewelsburg mosaic with the occult concept of the black sun, which had been introduced in the 1950s by the Landig Group as a replacement for the swastika and as a symbol for a mystic energy source that was supposed to renew the Aryan race. After the publication of the novel, the Wewelsburg symbol became popularly known as the "Black Sun".[1]