While it is nearly impossible to answer this question empirically, and with a great deal of certainty in terms of historicity, an educated guess is possible. It has been said that King Solomon (Book of 1 Kings) was one of the ten richest people in world history. According to the scripture, he collected over one billion dollars worth of gold per year when calculated with the value of gold today. Solomon inherited a vast amount of wealth from his father, King David, who should be considered a close second as far as biblical wealth goes. Solomon was also known for his excessive taxation policies which would have added to his wealth. The King of Israel also collected tribute from countries and kingdoms that he controlled. Solomon also had a lucrative business partnership with Hiram, the King of Tyre in which he collected a large booty every three years. It would not be an overestimation to calculate Solomon's wealth to be over $10 billion dollars.