Western Sudan Wikipedia
The Western Sudan is a historic region in the northern part of West Africa. Traditionally, the Western Sudan extends from the Atlantic Ocean across to the basin of Lake Chad (which is sometimes associated with a region called "Central Sudan" or other times with the Western Sudan) and includes the savanna and Sahel lands north of the West African tropical rainforest belt. It includes the rivers of the Senegal, Gambia and Niger systems, as well as the highlands of Fouta Djallon from which these rivers flow.
Historians have considered the Western Sudan as a land of great empires, since at least the seventh century, when the Empire of Ghana flourished, there have been a succession of empires: Ghana (seventh to eleventh century), Mali (thirteenth to fifteenth century), Songhai(1464–1591) are the three best known, but smaller large scale polities have also been important, the Empire of Great Foula (late sixteenth to early eighteenth century), the Bamana Empire (late seventeenth to early nineteenth century), and the nineteenth century empires of El Hajj Umar Tal and Samori Toure. In fact, since the fourteenth century at least, local historians of the region have seen its history in terms of a succession of empires. This cycle is discernible in the historical accounts of shaykh Uthman, whose history was told to the historian ibn Khaldun while on the Muslim Pilgrimage in 1397. It can also be found in the great Sudanese chronicle, Tarikh al-Fettash. Modern historians have followed suit, and the imperial tradition can be found in textbooks today.