For the history of the area pre-Nimba see: Liberia The Republic of Nimba started in 1989 as a trade agreement between the Gio and Mano tribes in the north of former Liberia. In 1996 Nimba was formed from these two tribal lands, named after the former County of Nimba in which the two tribes were based, it was joined by the Bassa tribe of coastal former Liberia (River Gee country) in 1998, Nimba spread further in 2004 to take in some of the western lands of Kpelle tribe (Bong and Grand Bassa Counties).