How rich is "Rich"?
There’s rich. There’s starting quarterback rich. And then there’s founder-of-Facebook rich.
Topping the list is Mansa Musa I, ruler of the Malian Empire until 1337. His net worth of $400 billion was amassed through his empire’s production of more than half of the world’s supply of gold and salt.
Many of the others on the list will be more familiar. Interesting.