kingdom of Kongo (kông´gō, kŏng´–), former state of W central Africa, founded in the 14th cent. In the 15th cent. the kingdom stretched from the Congo River in the north to the Loje River in the south and from the Atlantic Ocean in the west to beyond the Kwango River in the east. Several smaller autonomous states to the south and east paid tribute to it. Kongo was ruled by the manikongo, or king, and was divided into six provinces, each administered by a governor appointed by the manikongo.

In 1482, Diogo Cão, a Portuguese explorer, visited the kingdom, and the reigning manikongo, Nzinga Nkuwu, was favorably impressed with Portuguese culture. In 1491, Portuguese missionaries, soldiers, and artisans were welcomed at Mbanza, the capital of the kingdom. The missionaries soon gained converts, including Nzinga Nkuwu (who took the name João I), and the soldiers helped the manikongo defeat an internal rebellion.

The next manikongo, Afonso I (reigned 1505–43), was raised as a Christian and attempted to convert the kingdom to Christianity and European ways. However, the Portuguese residents in Kongo were primarily interested in increasing their private fortunes (especially through capturing Africans and selling them into slavery), and, despite the attempts of King Manuel I of Portugal to channel the efforts of his subjects into constructive projects, the continued rapaciousness of the Portuguese played a major part in weakening the kingdom and reducing the hold of the capital (renamed São Salvador) over the provinces.

After the death of Afonso, Kongo declined rapidly and suffered major civil wars. The Portuguese shifted their interest southward to the kingdom of Ndongo and helped Ndongo defeat Kongo in 1556. However, in 1569 the Portuguese aided Kongo by helping to repel an invasion from the east by a Lunda ethnic group. The slave trade, which undermined the social structure of Kongo, continued to weaken the authority of the manikongo.

In 1641, Manikongo Garcia II allied himself with the Dutch in an attempt to control Portuguese slave traders, but in 1665 a Portuguese force decisively defeated the army of Kongo and from that time onward the manikongo was little more than a vassal of Portugal. The kingdom disintegrated into a number of small states, all controlled to varying degrees by the Portuguese. The area of Kongo was incorporated mostly into Angola and partly into the Independent State of the Congo (see Congo, Democratic Republic of the) in the late 19th cent.

See J. K. Thornton, The Kingdom of Kongo (1983); A. W. Hilton, The Kingdom of Kongo (1985).