The Kingdom of Matamba (1631–1744) was a pre-colonial African state located in what is now the Baixa de Cassange region of Malanje Province of modern-day Angola. It was a powerful kingdom that long resisted Portuguese colonisation attempts and was only integrated into Angola in the late nineteenth century.
The first documentary mention of the Kingdom of Matamba is a reference to it giving tribute to the King of Kongo, then Afonso I of Kongo, in 1530. In 1535 Afonso subsequently mentioned Matamba as one of the regions over which he ruled as king in his titles. There is no further information on the kingdom's early history and modern oral traditions do not seem to illuminate this at the present state of research. However, it does not seem likely that Kongo had any more than a light and symbolic presence in Matamba, and its rulers were probably quite independent. Matamba undoubtedly had closer relations with its south southeastern neighbor Ndongo, then a powerful kingdom as well as with Kongo.
During the mid-sixteenth century Matamba was ruled by an unknown queen, who received missionaries from Kongo, then a Christian kingdom, dispatched by King Diogo I (1545–1561). Though this queen received the missionaries and perhaps allowed them to preach, there is no indication that the kingdom converted to Christianity.
The arrival of the Portuguese colonists under Paulo Dias de Novais in Luanda in 1575 altered the political situation as the Portuguese immediately became involved in Ndongo's affairs, and war broke out between Ndongo and Portugal in 1579. Although Matamba played a small role in the early wars, the threat of a Portuguese victory stirred the ruler of Matamaba (probably a king named Kambolo Matamba) to intervene. He sent an army to aid Ndongo against the Portuguese, and with these forces the combined armies were able to defeat and rout Portuguese forces at the Battle of the Lukala in 1590.
In 1618 the Portuguese governor of Angola, Luis Mendes de Vasconcelos, launched a large scale attack on Ndongo, using newly acquired Imbangala allies. The allied Imbangala, mercenary soldiers from south of the Kwanza River, turned the day and allowed Mendes de Vasconcelos' forces to sack Ndongo's capital and pillage the country. During the following two years, Mendes de Vasconcelos' son João led a detachment of Portuguese and Imbangala forces into Matamba where they did great damage. During this time the Imbangala band of Kasanje deserted the Portuguese and continued a campaign of destruction in Matamba. Thousands of Matamba subjects were killed and thousands more taken to America as slaves. It is during this period, for example that the ethnonym "Matamba" appears in slave inventories in Spanish America in considerable numbers.