Yusuf ibn Tashfin
Abu Bakr placed his cousin Yusuf ibn Tashfin in charge of Aghmat, and assigned him the responsibility of maintaining the front against the Zenata to the north. In a series of campaigns through the 1060s, while Abu Bakr held court in Marrakesh, Yusuf directed Almoravid armies against northern Morocco, reducing Zenata strongholds one by one. In 1070, the Moroccan capital of Fez finally fell to the Almoravids. Discontent, however, had arisen in the Almoravid ranks, particularly among the desert clans back in the Sahara, who regarded these distant northern campaigns as expensive and pointless. The Guddala tribe, who had earlier broken away from the Almoravid coalition, began urging other desert tribes to follow suit. After the fall of Fez, feeling Morocco was now secure, Abu Bakr decided it was time to return to the Sahara to quell the dissension in the desert homelands. He placed Yusuf ibn Tashfin in charge of Morocco in his absence. As was common among the Sanhaja tribes before extended military campaigns, Abu Bakr divorced Zaynab before he left, advising her to marry Yusuf if she needed protection.