As of 2026. OCHA and IOM reporting through 2026 continues to record several million displaced across the basin; the figure moves with each round of military operations, camp closures and returns.
The jihadist insurgency Boko Haram, founded in northeastern Nigeria in the early 2000s, launched an armed uprising in 2009 seeking to establish an Islamic state, and by the mid-2010s had seized territory across Borno, Adamawa and Yobe states and expanded operations into neighboring Cameroon, Chad and Niger around Lake Chad. A 2016 split produced the rival Islamic State West Africa Province (ISWAP). Insurgent attacks, mass abductions (including the 2014 kidnapping of 276 schoolgirls in Chibok), and government counterinsurgency operations have together displaced roughly 2.6-3 million people across the four-country Lake Chad Basin region, with around 2 million displaced within Nigeria alone, and have directly killed an estimated 35,000-40,000 people since 2009, with the wider humanitarian toll, including famine-linked deaths, considered substantially higher. The crisis remains active, with periodic upsurges in violence and displacement as of the mid-2020s.
The jihadist group Boko Haram, and its offshoot ISWAP, waged an insurgency based in northeastern Nigeria that spread into Cameroon, Chad and Niger; regional military operations also displaced civilians
Nigeria's 2006 census gave Borno 4.17 million, Yobe 2.32 million and Adamawa 3.17 million; Far North Cameroon held roughly 3.5 million and Diffa and Lac about 1.2 million between them, giving some 14-15 million around 2009. OCHA now describes a considerably larger affected population in the same areas, reflecting rapid growth over the intervening years.
UNDP's 2021 study estimated some 350,000 deaths attributable to the conflict in north-east Nigeria by end-2020, but roughly 314,000 of these were indirect — mainly children under five dying from the collapse of food, water and health systems — leaving about 35,000 direct conflict deaths. The 350,000 headline is routinely quoted as a killing toll, which UNDP explicitly did not claim; the Global Centre for the Responsibility to Protect earlier cited around 17,000 killed in the fighting. Figures cover Nigeria only, not Cameroon, Chad or Niger.
The ICC Prosecutor's December 2020 statement concluding the Nigeria preliminary examination named murder, rape and sexual slavery, enslavement, torture and child recruitment by Boko Haram and ISWAP, and murder, rape, torture, enforced disappearance, forcible transfer and illegal detention by Nigerian security forces; UNICEF, OCHA and Human Rights Watch have documented the same abduction and mass-killing patterns across the Lake Chad Basin.
Nigeria, Cameroon, Niger, Chad