Political map of Sub-Saharan Africa 23 August 1901 (Lake Chad Rendezvous): In 1899 the Nubian warlord Rabih az-Zubayr had antagonized the French by hanging one of their explorers (Ferdinand de Béhagle). After Rabih destroyed their punitive expedition (Battle of Togbao), the French sent three columns—one from each of their main African bases (Congo (Émile Gentil), Algeria (Amédée-François Lamy), and Senegal (Voulet–Chanoine Mission))—against his empire around Lake Chad. This time the French were successful: linking up their African empire (French Chad), killing Rabih (Battle of Kousséri), and chasing his son, Fadl-Allah, across the German-claimed north of Kamerun into British-claimed Northern Nigeria.