The Portuguese explorer Diogo Cão, sailing up the uncharted Congo River in 1483, had found Kongo villages and become the first European to encounter the Kongo kingdom.

During his visit, Cão had left his men in Kongo while taking Kongo nobles and bringing them to Portugal.

When he returned with the Kongo nobles in 1485, the ruling king, Nzinga a Nkuwu, had converted to Christianity.

Cão had returned to the kingdom with Roman Catholic priests and soldiers in 1491, baptizing Nzinga a Nkuwu as well as his principal nobles, starting with the ruler of Soyo, the coastal province.

At the same time a literate Kongo citizen returning from Portugal had opened the first school.

Nzinga a Nkuwu took the Christian name of João I in honor of Portugal's king at the time, João II.

The Kings of the Kongo, known as the mani-kongos, engage in trade with the Portuguese and host missionary activity, soon converting to Christianity.