The western and central Sudan in the early period

The Sudan (more precisely, bilād al-Sūdān, the land of the blacks) is the Arabic name for the trans-continental savannah belt, several hundred miles wide, lying between desert and forest. The Sudan has been the principal theatre for African Islamic history below the northern coast. Only rarely have Saharan movements exercised critical influence—e.g. the Almoravids (fifth/eleventh century) or the Sanūsiyya (nineteenth century). Only recently has Islam taken root in the forest: this is primarily a characteristic of the European colonial period, which checked local wars, opened roads, and encouraged trade and migrant labour—a situation equally true for Muslim penetration south from the savannah, or inland from the East African coast.

The Sahara, with its Berber population, has, however, been of crucial importance as an avenue of approach. The northern Sudan cities, Timbuktu, Gao and others, were ports facing the desert just as the eastern coastal cities faced the Indian Ocean. Gold for export, salt for import, were staples of Saharan trade. Several major routes crossed the Sahara: from Morocco to the goldfields of the upper Senegal and Niger; from Tunisia to the area between the Niger and Lake Chad; from Tripoli to Lake Chad; from Libya to Waday. The eastern Sudan, though closest to the heartlands of Islam, was penetrated last, perhaps because of difficulties of communication along the Nile, and the persistence of Christian states astride the river. Below the northernmost Sudanic strip, called the Sāhil or Coast, another pattern of Muslim mobility developed, chiefly east-west.