All of these regions and kingdoms became Islamic during the time period from 500 C.E. to 1500 C.E. except for the Kingdom of Ethiopia, which remained a stronghold of Christianity and continues to be predominantly Christian to this day.

The Kingdom of Ghana existed in the belt of West Africa that is rainforest. This is different to the rest of Africa which is either grassland (savannah) or desert. 

The Kingdom of Ghana collapsed around the thirteenth century due to weakening administration and conflict with surrounding peoples. In its wake a number of new kingdoms arose, but none more prominent than the Mali Empire. Centered around the capital of Timbuktu the Mali Empire grew rapidly in wealth, land and prominence. The most famous King of the Mali Empire was Mansa Musa who famously made a pilgramage to Mecca and gave away so much gold that he crumbled the Egyptian economy. 

Mali's time as a hegemonic power in West Africa was relatively short lived and their fall from grace coincided with the rise of the Songhai Empire. The Songhai Empire was centered around its capital in Gao. The height of the Songhai Empire was the fifteenth and early sixteenth centuries. The most famous rulers of Songhai were Askia and Sunni Ali. 

The West African Kingdoms of Mali and Songhai were Islamic Kingdoms. The Kings of both Empires made pilgrimages to Mecca, and Islamic law was enforced within their territories.

Mansa Musa was the ruler of Mali in the fourteenth century. He made a famous pilgrimage to Mecca, as all Muslims must do, and gave away so much gold during his time in Egypt that he crashed the Egyptian economy.

In the centuries following the death of the prophet Muhammad, the Islamic faith spread through Sub-Saharan Africa largely as a result of Muslim traders pushing their caravan routes further and further into the heart of Africa. The Kingdoms of Mali and Songhai (to provide two prominent examples) embraced Islam during this time period. 

Ibn Battuta lived during the fourteenth century. He is most widely known for his extensive travels throughout Africa and the rest of the known world. 

Genghis Khan conquered most of Asia and portions of the Middle East, establishing the massive Mongol Empire by his death in 1227 from the Pacific Ocean to the Caspian Sea. Less than a hundred years later, his grandsons and eventual successors began fighting among themselves, dissolving into multiple Mongol principalities.

The Chinese Mandate of Heaven suggests that the Chinese Emperor is divinely ordained to rule. This has the obvious implication that to challenge the power of the emperor would mean challenging someone with divine support. In Europe, this same philosophy was prevalent for much of the Middle Ages and the early period of Reformation. In Europe it was called "the divine right of kings."