Bateke kingdom controlling the Congo River around Pool Malebo and inland trade routes; signed French protectorate treaty in 1880.
Reduced to a French protectorate in September 1880 when King Iloo signed the Makoko Treaty with Pierre Savorgnan de Brazza, ceding territorial sovereignty; fully absorbed into French Congo by 1891–1892, ending the Tio Kingdom as an independent polity.
Definitive monograph on the Tio kingdom's political economy and social organization at the moment of French colonial contact; confirmed via AbeBooks, Amazon, Goodreads, Routledge, and Tandfonline review.