The early history of what is now the DRC is still largely unknown. The earliest inhabitants of the Congo Basin are believed to have been pygmies. Bantu groups moved into the area from the north and spread east and south beginning about 2,000 years ago. The northern Bantu groups settled in stateless communities in the rain forest. The Nilo-Saharan-speaking groups of the far north formed hierarchical systems with complex judicial structures. In the southern savanna zone, the Luba, Lunda, and other Bantu groups set up centralized kingdoms by 1500.

The first known state to emerge in what is now Zaire was the Luba kingdom, located in the Katanga region. The Luba kingdom was created in the 16th century when a warrior named Kongolo subdued the small chiefdoms in the area and accomplished a highly centralized state. To the northwest was the Kuba, a federation of numerous chiefdoms that reached its peak in the 18th century. The Kongo and Lunda kingdoms, which straddled Zairean territory, are more properly considered in the history of Angola.

In November 1965 a military coup took place in which General Mobutu Sese Seko overthrew President Joseph Kasavubu. Mobutu was able to restore political stability to the Congo, and by 1967 the Katanga rebellion had also been quelled. Under Mobutu, the name of the nation was changed to Zaire in 1971. In 1977 and 1978 Katangese rebels operating from Angola invaded the Shaba region but were repelled. By the late 20th century, the economic mismanagement and political corruption of Mobutu's regime had devastated the Zairean infrastructure and economy to the point that the nation had one of the lowest standards of living in the world.