Abu-Bakr Ibn-Umar (?-1088). Moroccan Almoravid ruler. He was appointed General of the Moroccan Murabit sect by its leader Ibn-Yasin on the death of his brother Yahya in 1056; captured Sus and Aghmat in southern Morocco in 1057, and became leader of the Murabit on the death of Ibn-Yasin in battle with the Berghwata Berbers in 1059; he subdued the Berghwata and sent a Murabit army northward under his cousin Yusuf Ibn-Tashfin while he raided south across the Sahara to West Africa in 1061; He allowed his cousin to continue autonomous operations after his own return from West Africa, subduing Ghana in 1076 and initiating the spread of Islam on the southern periphery of the Sahara; died shortly after receiving news of Ibn-Tashfin's victory at Zallaka near Badajoz, Spain in 1087. A leader of remarkable ability, he fused his tribes with a religious reform movement; his remarkable tolerance of Ibn-Tashfin's insubordination preserved the infant Almoravid (Murabit) state and permitted its rapid expansion into Muslim Spain and most of North Africa as well.