Organized Societies. During the first twelve hundred years of the Common Era, there appeared a procession of large, indigenously organized societies in the western, central, and eastern sections of West Africa, generally in the vicinity of the Senegal and Niger River basins or the region around Lake Chad. These societies included ancient Ghana, the Susu, Gao, Mali, Songhai, Kanem-Bornu, the Takrur, the Do or Dodugu, the Hausa, Kiri, the Mossi, and the Dagomba.

The Impetus for Empires. Though the rise and fall of Ghana, Mali, Songhai, Kanem-Bornu, the Hausa city-states, and the rest of the West African rulerships are frequently attributed to the trans-Saharan trade and the expansion of Islam, these factors alone do not explain the history of the region. It is true that trans-Saharan trade was of crucial importance in the origins and growth...