Final answer:
The Ghana Empire declined due to invasions by the Almoravids, political disintegration, and other internal challenges. It was succeeded by the Mali Empire, which was founded by the Mandinka people and rose to prominence under strong leaders and integration into Muslim trade networks.
Step-by-step explanation:
The decline of the Ghana Empire began around the 12th century due to a combination of factors including political disintegration with the rise of several petty kingdoms and the pressures of invasions by the Almoravids. Additionally, there were challenges such as internal strife and the exhaustion of resources that were central to Ghana's strength. The Mandinka people eventually came to power in the region, establishing the Mali Empire on the foundations of what was once Ghana. The Mali Empire, bolstered by leaders such as Sundiata Keita and Mansa Musa, thrived due to its integration into wider Muslim trade networks and its control over valuable trade commodities, unlike its predecessor.
After the fall of the Ghana Empire, Mali expanded its territory along the Niger river and played a prominent role in the trans-Saharan trade, thereby filling the power vacuum left by Ghana. The rise of the Songhai Empire later followed the eventual decline of the Mali Empire, where it grew larger and wealthier than Mali had been, controlling the important trade routes of West Africa.