The richest person in the world in 1991 is Taikichiro Mori who happened to have a $15 billion wealth.
Mori ventured the field of business after he left his job in a university. He was a professor in economics. He ventured building constructions. By the time that he was named by the popular magazine, he had 65 office buildings.

A Japanese billionaire was also named as the wealthiest person in the world for a time…