Who comes to mind at the phrase “richest man in history”? Some people might think of ancient rulers like Tsar Nicholas II of Russia or William the Conqueror. Other might consider more recent billionaires like Henry Ford, Andrew Carnegie, and Bill Gates. Those who are biblically-inclined might say King Solomon.
Celebrity Net Worth analyzed the 26 richest people who had ever lived by adjusting the inflation through time. Number one was a complete surprise to some, bearing a name many have never heard of: Mansa Musa I, with an estimated net worth of $400 billion. 
The Richest Person in History: African King Mansa Musa I
Musa lived from 1280–1337 and reigned over the Malian Empire in West Africa, which spans across modern-day Mali, Niger, Senegal, Mauritania, Burkina Faso, the Gambia, Guinea-Bissau, and Ivory Coast. 
“Contemporary accounts of Musa’s wealth are so breathless that it’s almost impossible to get a sense of just how wealthy and powerful he truly was,” said Rudolph Butch Ware, associate professor of history at the University of California.
Musa was born into a family of monarchs. His older brother, Mansa Abubakari Keita II ruled the empire until 1312 when he left for his pilgrimage to Mecca and an extra special expedition. He was intrigued with the Atlantic Ocean and the mysteries that awaited on the other side of it. He set off with a fleet of 2,000 ships and thousands of men, women, and slaves. Mansa Musa was appointed to take care of the empire in his absence
They never returned, leaving Mansa Musa to inherit the throne, a propitious change for their kingdom. Mali grew as they gained 24 new cities like Timbuktu.  The land was full of resources including gold and salt, which was the kingdom’s main exports. In fact, it held almost half of all the gold in the Old World, all of which belonged to the king.
“As the ruler, Mansa Musa had almost unlimited access to the most highly valued source of wealth in the medieval world,” said Kathleen Bickford Berzock, who specializes in African art at the Block Museum of Art at Northwestern University. “Major trading centres that traded in gold and other goods were also in his territory, and he garnered wealth from this trade.” 
The Journey That Made Mansa Musa Famous
Despite Mali’s natural riches, his empire was not a well-known one. Then Mansa Musa took his Hajj pilgrimage to Mecca, a journey that took him through the Sahara Desert, Egypt, and many cities along the way.
Musa traveled with an entourage of 60,000 men, the royal court officials, soldiers, entertainers, camel drivers, merchants, 12,000 slaves, flocks of sheep and goats for food, 100 camels, and horses. All of these people, including the slaves, wore gold brocades and expensive Persian silk. Each camel and horse carried a hundred pounds of pure gold on its back.
When the caravan reached Cairo, he made an entrance that can only be compared to Aladdin’s entrance to Agrabah in the Disney movie, except with quadruple the extravagance. Remember the part where Aladdin showered the parade watchers with gold coins? Mansa Musa did that as well during his three-month stay, eventually to the detriment of the area. He so lavishly handed out gold that he accidentally caused the value of metal to plummet, damaging the economy for the next ten years. 
On his way back home, Mansa Musa tried to rectify his mistake by borrowing the gold back at high interest rates.
His generosity did not earn him favor with the Malian griots, who were minstrels and storytellers, according to Lucy Duran of the School of African and Oriental Studies in London.
“He gave out so much Malian gold along the way that jelis [griots] don’t like to praise him in their songs because they think he wasted local resources outside the empire,” she said.
Despite the crashed economy and disgruntled griots, the king’s generosity had put him and his kingdom on the map. Timbuktu earned a reputation of a lost city of gold like that of El Dorado, bringing fortune hunters and explorers from Europe to see the mythical city in the 19th century. 
Education and Religion
Spreading Islam and proper education was a big focus of Mansa Musa. He built mosques, schools, libraries, and universities throughout his empire and along his journey to Mecca.  Some of these mosques still stand today. Legend has it that he built a new mosque every Friday for over twenty years.
It’s unbelievable to note how detached Mansa Musa was from his wealth, as he gave it away to citizens and to fund buildings. 
However, these riches did not last after the ruler’s death at the age of 57. Musa’s heirs were unable to stop civil wars and invaders. It took only two generations for the record-breaking wealth to vanish . The arrival of Europeans was the last blow that cause this once prosperous empire to crumble.
“Had Europeans arrived in significant numbers in Musa’s time, with Mali at the height of its military and economic power instead of a couple hundred years later, things almost certainly would have been different,” says Lisa Corrin Graziose, director of the Block Museum of Art. 
Overall, it’s hard to conceive how much wealth and land this man actually possessed.
University of Michigan associate history professor Rudolph Ware explained: “Imagine as much gold as you think a human being could possess and double it, that’s what all the accounts are trying to communicate,” he said. “This is the richest guy anyone has ever seen.” 
- Brian Warner. The 25 Richest People Who Ever Lived – Inflation Adjusted https://www.celebritynetworth.com/articles/entertainment-articles/25-richest-people-lived-inflation-adjusted/ April 14, 2014
- John Hall. Meet Mansa Musa I of Mali https://www.independent.co.uk/news/world/world-history/meet-mansa-musa-i-of-mali-the-richest-human-being-in-all-history-8213453.html October 16, 2012
- Naima Mohamud. Is Mansa Musa the richest man who ever lived? https://www.bbc.com/news/world-africa-47379458 March 10, 2019
- Thad Morgan. This 14th-Century African Emperor Remains the Richest Person in History https://www.history.com/news/who-was-the-richest-man-in-history-mansa-musa March 19, 2018