One of the very few centralised states of the equatorial forest margin: Mangbetu-speaking elites unified their clans in the late 1700s, and King Nabiembali then conquered Mangbele, Madi, Bangba, Mayogo and Barambo neighbours, binding them in by marrying their women and installing his sons over their mothers' peoples. His sons revolted and killed him in 1859, splintering the realm into successor kingdoms.
Absorbed: the successor kingdoms fell under Egyptian authority in the late 19th century, regained brief independence during the Mahdist upheaval, and were integrated into the Congo Free State in 1892.
University of Washington Press / American Museum of Natural History volume and the standard modern scholarship on Mangbetu history and courtly culture; verified via Open Library /works/OL4449311W.
The first European account of the Mangbetu court, from the 1870 visit to King Mbunza — the primary source behind all later descriptions; verified via Open Library /works/OL1472033W.