Which kingdom was established on the Niger River?

The name of the Kingdom which was established or flourished on the Niger River was Mali Kingdom.

Explanation:

It was a kingdom which was established in West Africa during the 1235 to 1670. Mali kingdom which became the largest empire of West Africa was started as a small Mandinka state at the upper end of the Niger River, centered on the city of Niani (the name of the empire in Manding). This empire influenced the entire Africa with its custom, rules and language. This empire was founded by the Sundiata Keita.