Muhammad Ahmad, the Mahdi of the Sudan, was the African Muslim best known to the outside world in the nineteenth century. Preacher, teacher, and writer, he lived just over forty years (1844–85) but left an indelible imprint on his native region. He drew on his understanding of Islam to mobilize a major portion of the Muslim population against foreign intrusion and economic decline. He understood that God was calling him to be the Mahdi, the rightly guided one who comes during the troubled times at the end of the world.

The imperialism he faced goes by the name of the Turko-Egyptian regime or Turkiyya. The Sudanese, over the course of the nineteenth century, came to use the expression “Turk” to refer to all of the people of Turkic, Slavic, Arab, or European origin associated with the regime and its exploitation. Egypt, still officially part of the Ottoman Empire, began to expand in the early nineteenth century after Napoleon's invasion and under the direction of Muhammad Ali (see Chapter 6). From Cairo and a southern base in Khartoum, Muhammad Ali commissioned traders to find sources of slaves and ivory in the upper reaches of the Nile and support the dramatic modernization process of Egypt. Beginning in the 1820s these entrepreneurs explored, traded, and raided in the vast marshes of the Upper Nile. They set up villages and factories in the northern or Arabic-speaking areas of the Sudan and preyed upon the small-scale societies to the south (see Map 5).