Witchcraft is the human exercise of alleged supernatural powers for antisocial, evil purposes (so-called black magic). A female held to have such powers may be called a witch or sorceress, the male counterpart being named wizard, sorcerer, or warlock. Belief in witchcraft survives in modern technologically developed cultures and remains a potent factor in most nonliterate societies.

In ancient Greece witchcraft is mentioned as early as Homer. The best known sorceress in classical times was the legendary Medea. The Roman poet Horace left an elaborate description in Satires of the proceedings of two witches in the Esquiline cemetery. The Bible contains a number of references to witchcraft, a notable example being the so-called Witch of Endor consulted by King Saul (I Sam. 28). The early Church Fathers generally held that any so-called witchcraft was a delusion and a deception and that the name of Jesus used by a believing Christian could turn aside attempted witchcraft. This attitude was accompanied by strong disapproval of the practice, as shown in church canons. Clergy were urged to preach that claims of witchcraft were false, for God alone is powerful, and that there is a sharp distinction between factual evidence and fantasy or dreams.

In the following centuries, however, belief in witchcraft spread, perhaps encouraged by the very sermons preached against it, which put ideas into the heads of simple people who had previously never heard of such possibilities. The connection with Satan was emphasized with the rise of the dualist heresy, which ascribed real power to the devil as an equal opponent of God. Once witchcraft was believed to involve demonic possession, heresy, and the rejection of God, it came within the scope of the Inquisition. From the late Middle Ages to the early 18th century, vehement opposition to the witch cult was demonstrated throughout Europe in public "trials" and executions, conducted on the basis of the biblical injunction "You shall not permit a sorceress to live" (Ex. 22:18). Many of those who denounced these measures, pointing to psychological factors at the root of alleged evidence, were themselves burned at the stake. Victims of the witchcraft trials have been variously estimated to number from the hundreds of thousands to the millions.

Belief in witchcraft was taken to colonial America by English settlers. In 1692, after a prolonged witch trial at Salem, Mass., as a result of accusations by a group of teen-age girls, more than 30 persons were convicted of witchcraft, some after torture. Scattered claims of witchcraft continued to be heard from Europe and the Americas into the 20th century.

Belief in witchcraft is almost universal in nonliterate societies. Among some peoples individuals will openly avow that they are witches and make public threats; more frequently, personal knowledge of the techniques is denied, and witchcraft is the subject only of hushed gossip. In the 19th and 20th centuries, the worldwide phenomenon was the subject of extensive anthropological investigation.