Almoravid rule brought the tribes of the western Sahara and the settlements of the far Maghrib under the authority of a single leader and a government based in the newly founded capital of Marrakesh (c. 1070). The Almoravid movement of the early eleventh century and the Almoravid rulers Yusuf ibn Tashufin and his son and successor Ali defined their legitimacy in terms of the extension of the jurisdiction of Sunni (Maliki) law among the Sanhaja tribes and upholding the proper practice of religion and rule of law. The incorporation of al-Andalus into Almoravid rule allowed for access to the legal-religious expertise of Maliki jurists of the former Taifa cities, especially Cordoba, the former Umayyad capital and seat of the qadi al-jama` and his shura. Jurists in Cordoba collaborated with the Almoravid regime in the extension of Maliki law and in the assertion of their authority in legal interpretation. Ibn Rushd al-Jadd, in particular, strived to promote the authority of jurists who specialized in usul al-fiqh (the sources and principles of jurisprudence) over those who used the Maliki “mother texts” to interpret law in particular cases and sometimes used their own legal judgment (ra’y) where the texts did not provide clear and unequivocal guidance. Ibn Rushd’s effort to reform the practices of legal interpretation were both advanced by Almoravid rule and the achievement of a legal “system” that encompassed all of al-Andalus and the far Maghrib and challenged by practical constraints, particularly in the hinterlands, that required compromise. The paper will develop the argument by looking at evidence of how Maliki law was interpreted according to the mother texts and efforts to discipline that practice, comparing a fatwa issued in the tenth century by the Qayrawani jurist Ibn Abi Zayd about their usage with a few issued by Ibn Rushd al-Jadd on the same subject. Resistance to “usuli” efforts at reform generated a discourse about interpretation and practice that accommodated a spectrum. The paper provides a view of professional differentiation and contestation in a diverse legal landscape that contributes to our understanding of the establishment of Maliki law in the western Sahara and offers another perspective on the rise of the Almohads. Sources include fatwa collections: Fatawa Ibn Rushd; Fatawa al-Burzuli; al-Wansharisi, al-Mi`yar al-mu`rib; Ibn Abi Zayd’s collection of masa’il al-Nawadir wa-l-Ziyadat, and reference to historical narratives such as al-Marrakushi, al-Mu`jib fi talkis akhbar al-Maghrib