There is a leadership struggle underway within Boko Haram, the violent, extremist movement that has claimed more than 20,000 lives since 2011 and destabilized the secular Nigerian state and its neighbors. The personal struggle between Abubakar Shekau and Abu Musab al-Barnawi reflects in part the rivalry between Boko Haram and a splinter group, “Ansaru,” and are part of a complex, intra-Muslim conflict across the Sahel, including competition between rival al Qaeda in the Islamic Maghreb (AQIM) and the Islamic State.