Among the Bantu of the Congo Basin, Nkisi (a.k.a. Nkishi) (plural varies minkisi, zinkisi or nkisi [concords with mi-] according to dialect) is the general name for a spirit, or for any object that spirit inhabits. It is frequently applied to a variety of objects used throughout the Congo Basin in Central Africa thought to contain spiritual powers or spirits. The term and its concept have passed with the slave trade to the Americas, especially Latin America (in Palo Mayombe the spirits of nkisi are often called "mpungo").
The current meaning of the term derives from the root, *-kitį- referring to a spiritual entity, or material objects in which it is manifested or inhabits in Proto-Njila, an ancient subdivision of the Bantu language family.
In its earliest attestations in Kikongo dialects in the early seventeenth century it was spelled "mokissie" (in Dutch), as the mu- prefix in this noun class were still pronounced, and was reported by Dutch visitors to Loango as referring both to a material item and the spiritual entity that inhabits it. In the sixteenth century, when the Kingdom of Kongo was converted to Christianity, ukisi (a substance having characteristics of nkisi) was used to translate "holy" in the Kikongo Catechism of 1624.
In the eighteenth century, the mu- prefix evolved into a simple nasal n-, so the modern spelling is properly n'kisi, but many orthographies spell it nkisi (there is no language wide accepted orthography of Kikongo).
Close communication with ancestors and belief in the efficacy of their powers are closely associated with minkisi in Kongo religion. Among the peoples of the Congo Basin, especially the Bakongo and the Songye people of Kasai, exceptional human powers are frequently believed to result from some sort of communication with the dead. People known as banganga (singular: nganga) work as healers, diviners, and mediators who defend the living against witchcraft and provide them with remedies against diseases resulting either from witchcraft or the demands of bakisi (spirits), emissaries from the land of the dead.
Banganga harness the powers of bakisi and the dead by making minkisi. Minkisi are primarily containers - ceramic vessels, gourds, animal horns, shells, bundles, or any other object that can contain spiritually-charged substances. Even graves themselves, as the home of the dead and hence the home of bakisi, can be considered as minkisi. In fact, minkisi have even been described as portable graves, and many include earth or relics from the grave of a powerful individual as a prime ingredient. The powers of the dead thus infuse the object and allow the nganga to control it. The metal objects commonly pounded into the surface of the power figures represent the minkisis' active roles during ritual or ceremony. Each nail or metal piece represents a vow, a signed treaty, and efforts to abolish evil. Ultimately, these figures most commonly represent reflections upon socially unacceptable behaviors and efforts to correct them. 
The substances chosen for inclusion in minkisi are frequently called "bilongo" (singular nlongo, plural is also milongo) a word often translated as "medicine." However, their operation is not primarily pharmaceutical, as they are not applied to or ingested by those who are sick, and perhaps bilongo is more accurately translated as "therapeutic substances.". Rather they are frequently chosen for metaphoric reasons, for example, bird claws in order to catch wrongdoers, or because their names resemble characteristics of spirits in question. Often the contents of minkisi were chosen because their names sounded similar to the specific goals of the nkisi and illustrated a play on words.
Among the many common materials used in the minkisi were fruit ("luyala" in Kikongo - which is similar to "yaala," which means "to rule"), charcoal ("kalazima" in Kikongo - which is similar to "zima," which means "to strike or extinguish"), and mushrooms ("tondo" in Kikongo - which is similar to "tondwa," which means "to be desired, thanked or praised"). Minerals were collected from various places associated with the dead, such as earth collected from graves and riverbeds. White clay was also very important in the composition of minkisi due to the symbolic relationship of the color white and the physical aspects of dead skin as well as their moral rightness. White contrasted with black, the color of negative ideas and concepts. Some minkisi use red ochre as a coloring agent. The use of red is symbolic of the mediation of the powers of the dead.
Minkisi serve many purposes. Some are used in divination practices, rituals to eradicate evil or punish wrong-doers, and ceremonies for protective installments. Many are also used for healing, while others provide success in hunting, trade, or sex. Important minkisi are often credited with powers in multiple domains. Most famously, minkisi may also take the form of anthropomorphic or zoomorphic wooden carvings, and it is these that have principally interested art historians.
Minkisi and the afflictions associated with them are generally classified into two types. Some are "of the above," and some are "of the below." The "above" minkisi are associated with the sky, rain and thunderstorms. Those "of the below" are associated with earth and waters on land. The minkisi "of above" were considered masculine and were closely tied to violence and violent forces. They seemed to hold a higher importance; at least according to the masculine members of the culture who wrote on the subject.
Birds of prey, lightning, weapons, and fire are all common themes among the minkisi of the above. They also affected the upper body. Head, neck, and chest pains were said to be caused by these nkisi figures. Some figures were in the form of animals. Most often these were dogs, referred to as Kozo. Dogs are closely tied to the spiritual world in Kongo theology. They live in two separate worlds, the village of the living, and the forest of the dead. Kozo figures were often portrayed as having two heads. This was symbolic of their ability to see both worlds.
The purpose of the minkisi of the above was largely civil in nature. They were used to maintain order and seal treaties.
Nkondi (plural varies according to dialect Minkondi, zinkondi) are a subclass of minkisi that are considered aggressive. Because many of the nkondi collected in the nineteenth century were activated by having nails driven into them, they were often called "nail fetishes" in travel writing, museum catalogs and art history literature. Many nkondi also feature reflective surfaces, such as mirrors, on their stomach areas or the eyes, which are held to be the means of vision in the "Other World." Although they can be made in many forms, the ones featuring a human statue with nails are the best described in anthropological and scholarly literature.
Nkondi are evoked to search out wrongdoing, enforce oaths, and cause or cure sicknesses. Perhaps the most common use was the locating and punishing of criminals, by hunting down wrongdoers and to avenging their crimes. An oath taker may declare him or herself vulnerable to the disease caused by an nkondi should he or she violate the oath. People who fall sick with diseases known to be associated with a particular nkondi may need to consult the nganga responsible for mediating with that spirit to determine how to be cured.
Although nkisi nkondi have probably been made since at least the sixteenth century, the specifically nailed figures, which have been the object of intensive collection in Western museums, nailed nkondi were probably made primarily in the northern part of the Kongo cultural zone in the nineteenth and early twentieth centuries. They were the targets of intense collection probably because of the drama of the nailing and the mysterious awe that the mirrored eyes had for collectors, many of whom were not particularly aware of their specific function. Very few if any new ones are being made today, with the exception of purely artistic representations.
Modern impact 
Central African beliefs migrated to the Americas with the slave trade, and a number of the Neo-African religions of the Americas have Kongo elements, most notably Palo Mayombe in Cuba and elsewhere. In their American forms there are often substantial variations from the forms encountered in Africa, but the general logic is quite similar.
The nkisi figures brought back to Europe in the nineteenth century in particular caused great interest in stimulating emerging trends in modern art, and African themes previously considered primitive or ugly were now viewed as aesthetically interesting. The pieces became influential in art circles and many were acquired by art museums. The intentions of the banganga who created minkisi were practical, that is their characteristics were dictated by the need of the object to do the work it was required to do—hence the nails which caused a sensation were never seen as decorative items but as a requirement of awakening the spirit; or the gestures were part of a substantial metaphor of gestures found in Kongo culture.
Recently some modern artists have also been interested in creating nkisi of their own, most notably Renee Stout, whose exhibition "Astonishment and Power" at the Smithsonian Institution coupled her own versions of nkisi with a commentary by noted anthropologist Wyatt MacGaffey.
- Nkisi in Palo Mayombe
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