Wicca is a Neopagan religion and a form of modern witchcraft. It is often referred to as Witchcraft or the Craft by its adherents, who are known as Wiccans or Witches. Its disputed origins lie in England in the early 20th century, though it was first popularised during the 1950s by Gerald Gardner, a retired British civil servant, who at the time called it the "witch cult" and "witchcraft," and its adherents "the Wica." From the 1960s the name of the religion was normalised to "Wicca." Wicca is typically a duotheistic religion, worshipping a Goddess and a God, who are traditionally viewed as the Triple Goddess and Horned God. These two deities are often viewed as being facets of a greater pantheistic Godhead, and as manifesting themselves as various polytheistic deities. Nonetheless, there are also other theological positions within the Craft, ranging from monotheism to atheism. Wicca also involves the ritual practice of magic, largely influenced by the ceremonial magic of previous centuries, often in conjunction with a liberal code of morality known as the Wiccan Rede, although this is not adhered to by all Witches. Another characteristic of the Craft is the celebration of seasonally based festivals known as Sabbats, of which there are usually eight in number annually.

The great central act of Christian worship is the Mass, a Sacrifice which can be offered to God alone, and the climax of the sabbat orgies is the horror of the black mass, a sacrifice of mockery, impiety, and blasphemy which is offered to the Devil. Satanists today often meet with the celebration of the black mass as their main object, and it is indeed the culmination and to use a term of the schools the very quiddity of devil-worship and the cult of hell. In detail the black mass imitates, so to speak and foully parodies with every circumstance of crapulous obscenity and contempt the Sacrifice of Calvary. The black mass today is sometimes celebrated in a cellar, but Satanists have become so audacious and so strong in evil that the largest room in their houses is known to be permanently fitted up for these abominable mysteries. In one case the room is draped with black hangings and the windows are always shuttered with curtains drawn.