Hausa Kingdoms
The Sudanic States emerged from the wake of the upheaval that transformed the system of governance in the central Sudan to patriarchal system. With influence of Islamic Mali Empire, the Hausa Kingdoms were replaced beginning with the Kingdom of Kano by a set of sultanates in the 11th century. The rise of the Sultanates led to series of wars that periodically saw the emergence of organised Empires in Northern Nigeria, by the 17th century, however, these empire had debilitated their economies and have largely stagnated. The parallel rise Fula influence resulted in a wave of ethnic Jihads that saw the rise of the Sokoto Caliphate encompassing much of Northern Nigeria and Northern Cameroon.