In spirit possession, nonhuman forces or entities are believed to enter a person's body and affect his or her actions. Western cultures usually view possession as a sign of madness or evil. But in Africa, spirit possession is considered a form of communication between people and spirits that has important religious, social, and political meaning.
Although it is believed that the spirits that possess people have greater powers than humans, they are not considered gods. In some cultures they are ancestors or mythical heroes; in others they are foreign beings. The spirits signal their presence through illness, dreams, sudden avoidance of certain items or practices, or the appearance of several distinct personalities in one person (the host). Spirits considered harmful may be exorcised, or removed. However, in many cases the spirit's host accepts possession.
When possession is accepted, a ritual of accommodation is usually performed in which the spirit is summoned and invited to take over the host's body. The host enters a trance followed by a period of total or partial amnesia. The spirit may demand that the host wear certain clothes, eat certain foods, or perform certain activities on a regular basis. Afterwards, the possessed individual often becomes a medium through which the spirit communicates on certain social or religious occasions.
There are several theories about the meaning and purpose of spirit possession. Among some groups, possession is an important religious activity that uses spirits to uphold the moral order of society. An official priesthood, typically male, interprets the communication between the spirit and human worlds. Other cultures see it as a way to deal with personal problems such as illness or infertility.
Ultimately, spirit possession provides a powerful form of communication within African societies. Through possession, the spirits of heroes or ancestors pass on cultural knowledge that unifies members of a group. Spirits representing outside forces, such as different religious or political systems, express new ideas and discuss new practices. Possession can serve as a force of resistance—encouraging people to avoid new ideas—or a force of change—encouraging them to adopt or adapt new ideas. (See also Death, Mourning, and Ancestors; Healing and Medicine; Mythology; Religion and Ritual; Taboo and Sin; Vodun; Witchcraft and Sorcery.)