John Davison Rockefeller was world's 1st billionaire
John Davison Rockefeller, the founder of Standard Oil refinery, became the first billionaire in modern history on September 29, 1916. He founded Standard Oil in 1870, which split into firms like ExxonMobil and Chevron, making him a billionaire. According to Time, he is still one of the richest people ever, with an estimated wealth of $340 billion (adjusted, 2015).