How did the niger river impact the development and growth of the west african kingdoms

The Niger River has impacted the development and growth of the West African Kingdoms in many ways. It has given the people a suitable ecosystem to live on, suitable for agricultural works. The ecosystem has given the people of West Africa a place to live in and to use it for their advantage. The Niger River also became the passageway of trades across the regions. The trade system was known as Trans-Saharan Caravan Trade, wherein the merchants at that time travelled by caravan through the Sahara Desert. 

b) race riots in several cities