The study of the long-term history of what has been known since 1960 as the Islamic Republic of Mauritania is possible largely because of inhabitants’ early embrace of Islam in the 8th century. While research on the early pre-Islamic history of the region is limited by the availability of sources to primarily the archaeological, the arrival of Islam through trade networks crossing the Sahara from North Africa meant that Arab merchants and explorers supplied and produced knowledge about the region’s inhabitants, polities, and natural resources that was then written down in Arabic by Muslim chroniclers and historians. Early Muslims were largely Kharijite and Ibadi but the 11th-century Almoravid reformist and educational movement ensured that the region’s Muslims would predominantly follow Sunni Islam as defined by the Maliki school of law and ʿAshari theology. By the time the Almohad empire succeeded the Almoravid in the 12th century, important centers of Islamic scholarship were emerging in major trading towns in the Sahara and along the Senegal River. The expansion of Sufi thought and practice, the arrival of the Arabic-speaking Banu Hassan, and the subsequent development of political entities known as emirates occurred in ensuing centuries and played a part in the genesis of a social structure that valorized the Arabic language, the study of Islam, and claims of descent from the Prophet Muhammad. The arrival of European merchants in the 15th century and the subsequent colonization of the region by the French led to rapid changes in the economic and cultural bases of political authority and social hierarchy, with colonial policy largely valorizing Sufi leaders as political interlocutors and community representatives. Independence from France in 1960 meant the establishment of an Islamic Republic whose laws are based on a mixed legal system of Maliki Islamic and French civil law. The basis of presidential rule is not religious in nature, though presidents have increasingly used a discourse of religion to legitimize their rule in the face of internal political opposition and external threats from extremist groups such as al-Qaʿeda.