In Europe, the 1300s were dark days — a period of religious insularity and superstition made even worse by the arrival of the Black Death, an outbreak of bubonic plague that killed an estimated 50 million people on the continent alone. Meanwhile, thousands of miles away in sub-Saharan Africa, the Mali Empire was experiencing a medieval flourishing of culture and learning fueled by unimaginable wealth.
At the center of it all was a West African king named Mansa Musa, who reigned over a vast Muslim empire stretching 2,000 miles (3,219 kilometers) from the Atlantic Ocean to modern-day Niger. But more important than the size of Mansa Musa's empire was the richness of his natural resources — two highly productive gold fields renowned for producing the purest and most coveted gold in the world.
If the stories told about Mansa Musa are true — that he and his court were bedecked in pure gold, and that he spent so much gold on a pilgrimage to Mecca that he devalued the price of gold for decades — then he may have been the richest man to ever live. The website Celebrity Net Worth says he was worth $400 billion in today's dollars, making Mansa Musa nearly four times as rich as Jeff Bezos.