Dugu, in Arabic Duku, is the eponymous ancestor of the Duguwa dynasty, called in the Arabic sources the Banu Duku. Appearing as the third ruler in the Diwan, he gives his name to the first royal line of Kanem, identified by modern scholars with the Zaghawa kings whom ninth- and tenth-century Arab geographers such as al-Yaqubi and al-Muhallabi located east of Lake Chad. Those geographers report that the Zaghawa held their king in awe as a sacred person, a sovereign hidden from common sight and believed to command life and death, a pattern of divine kingship that underlies the later Sefuwa institution of the mai. The Duguwa ruled until the eleventh century, when the line of Muslim mais descended from Hummay displaced them.