Evidence exists of early forms of urbanization in Western Sudan along the Sahel, a climatically transitional band stretching across Africa between the Sahara Desert to the north and the Sudanian savanna (grasslands) to the south. The first accounts of the existence of states in this region appear in Arab writings of the eighth century AD. By the eleventh century AD, Arabs and Berbers of faraway North Africa knew of the Wagadu Empire and its wealthy and powerful ruler called the ghana. The Wagadu kingdom was followed by the larger empire of Mali, and later still by the empire of Songhai.

The broad flat expanse of the Western Sudan enables the placid Niger River to meander in its sweeping arc from west to east, making the river ideally suited to human navigation. This topography has also allowed for the easy movement of peoples, languages, animals, crops, arts, and ideas. The dramatic diversity of temperature and climate that separates broad strips of territory has encouraged economic specialization within each region. Pastoralists (animal herders) living on the edge of the desert in the Sahelian city of Timbuktu are only 200 kilometers north of the fertile floodplain of the Niger River. Farmers on the savanna below the Niger are in turn only a few hundred kilometers from the edge of the great equatorial rain forest. Throughout the long history of the Western Sudan, the proximity of these disparate zones has made trade crucial to the prosperity of settled communities. Protein-deficient farmers of the savanna needed meat from their pastoral neighbors and salt from desert nomads. Nomadic herders of the Sahel needed the cereals produced by the farmers and exchanged them for the meat and hides of their livestock. Forest dwellers traded meat and skins from the animals they hunted, as well as foodstuffs from forest crops. Fishermen of the Niger sent their protein-rich catches in all directions. This regional interdependence encouraged commerce, economic specialization, and in strategic locations, the creation of towns, cities, and states (societies with centralized political authority, a ruling class, and urban centers). These trading relationships were forged centuries before Arab writers ever heard of the wealth of the ghana

However, until recent times most scholars attributed the rise of Sudanic states to the introduction of the camel into the Sahara around the fourth century AD. Camels brought the first Arab travelers to the previously unknown empires of the Sudan, thereby providing historians with the earliest written evidence of their existence. Armed with these documents, they assumed that the cities of the Sudan had emerged in response to the needs of Arab and Berber desert traders. Before the appearance of the rare and exotic goods supplied by the trade, scholars reasoned, rulers lacked the leverage they needed to elevate themselves in the eyes of their followers. Such an interpretation argued against common sense, as it is unlikely that merchants would chance the arduous trip across the desert if there were no urban markets to attract them, but it was supported by the few written sources available, all of which were produced by literate outsiders who traveled into the region after the advent of camel commerce.

Recent archaeological excavations have revealed that the Western Sudan had thriving urban centers before the first camels made their way across the desert. Indeed, at Jenne on the Middle Niger, archaeologists have uncovered a sprawling urban settlement that lacks the monumental architecture, elaborate tombs, and memorials to powerful individuals that are associated with contemporary Near Eastern and Nile Valley remains. Instead, the settlement pattern suggests a diffusion of political power and a remarkable degree of social and economic equality. Although some archaeologists question whether or not such settlements constitute true urbanization, others see in Jenne a remarkable example of social complexification without state-sponsored coercion.

Although there can be no doubt that complex societies emerged in the Western Sudan before the advent of camel-borne commerce, the integration of the camel into the trans-Saharan caravan trade stimulated political expansion in the region. The quickening pace of economic activity spurred urbanization and encouraged economic specialization, which in turn demanded greater political authority to safeguard the merchants and the indigenous elite who participated in the trade. Merchants at both the northern and southern markets required security, without which commerce could not continue, let alone flourish.