History of Chad Africa's major language groupings south of the Sahara Desert (except Khoisan, which is not considered a valid genetic grouping anyway), i. e. the Afro-Asiatic, Nilo-Saharan and Niger–Congo phyla, originated in prehistoric times in a narrow band between Lake Chad and the Nile Valley. The origins of Chad's peoples, however, remain unclear. Several of the proven archaeological sites have been only partially studied, and other sites of great potential have yet to be mapped. At the end of the 1st millennium AD, the formation of states began across central Chad in the sahelian zone between the desert and the savanna. For
Chad–Nigeria relations the wake of the Chibok schoolgirl kidnapping, Chad's minister of national defense, Benaindo Tatola, met with Cameroon's defense minister Edgard Allain Mebe Ngo'o in Yaounde. "Ngo'o said Chad had also deployed troops to work together with Cameroonian forces on the borders with Nigeria. He also said troops from the two countries will cross into Nigeria and fight Boko Haram in collaboration with Nigerian forces." Chad–Nigeria relations Nigeria considered France its primary rival in its attempt to chart the course of West Africa's political development. Its generally paternalistic relations with Chad intensified after the coup that ousted President François Tombalbaye in