Since the 10th century, the Batéké and other Bantu tribes that had migrated from Nigeria settled in the lower Congo Basin. The Kingdom of Kongo likely emerged around 1370, founded by Ntinu Wene (also known as Lukeni). He was the first to conquer the kingdoms of Mbundu and Mpemba, where he established the capital, Mbanza Kongo. Later, he incorporated additional kingdoms into his realm through treaties, which then formed a federation of four constituent states. Without an independent and functional state large enough to counter the increasing activities of European colonial powers in the Congo Basin, Central Africa was largely defenseless. As a result, by the early 18th century, the slave trade was able to expand undisturbed and systematically by Europeans, Afro-Arabs, and some African peoples from the early 16th century until the mid-19th century.