![Niger soldiers after violent engagement with Boko Haram.](/sites/default/files/styles/large/public/Militaire_nige%CC%81riens_contre_Boko_Haram%2C_mars_2015..jpg?itok=KI1LtV7p)
Niger soldiers after violent engagement with Boko Haram, 2015
![Weeping fathers of kidnapped girls in Chibok.](/sites/default/files/styles/large/public/Parents_of_Chibok_kidnapping_victims.png?itok=M9saAnP9)
Weeping fathers of kidnapped girls in Chibok, 2014
![Illustration of Kanem-Bu warriors.](/sites/default/files/styles/large/public/Group_of_Kanem-Bu_warriors.jpg?itok=bHA2-_9T)
Kanem-Bu warriors, 1892
![Dixon Denham and Hugh Clapperton meet the Shehu of Borno.](/sites/default/files/styles/large/public/ElKanemi-1823-ReceptionDenhamClapperton.jpg?itok=qEyzBunu)
Dixon Denham and Hugh Clapperton meet the Shehu of Borno, Muhammad al-Amin al-Kanami 1823
![First Lady Michelle Obama making a plea for the return of the Chibok girls.](/sites/default/files/styles/large/public/Michelle-obama-bringbackourgirls.jpg?itok=9Y3bFjye)
First Lady Michelle Obama making a plea for the return of the Chibok girls, 2014
![Records of the formation of the Sokoto Caliphate.](/sites/default/files/styles/large/public/forming%20the%20caliphate.jpg?itok=JKh6tAzQ)
Records of the formation of the Sokoto Caliphate, circa 1754-1817
![Muhammad Al Amin ibn Muhammad al-Kanami.](/sites/default/files/styles/large/public/Mohammed_el-_Amin_el-Kanemi_1826.jpg?itok=PBeURGhT)
Muhammad Al Amin ibn Muhammad al-Kanami
![Bukar Garbai ibn Ibrahim.](/sites/default/files/styles/large/public/Shehu_Abubakar_Garbai_of_Borno.jpg?itok=kW8t1hfC)
Bukar Garbai (or Abubakar Garbai) ibn Ibrahim
![The workings of the oil industry in Port Harcourt, Nigeria.](/sites/default/files/styles/large/public/Gates_of_Oil_reifnery_in_Port_Harcourt.jpg?itok=nBUMgq-V)
The workings of the oil industry in Port Harcourt, Nigeria