Rockefeller John D was formerly the world's wealthiest man. The world's first billionaire.
By the age of 25, he had amassed control of one of the nation's major oil refineries. By the time he was 31, he had risen to become the world's greatest oil refiner. By the age of 38, he controlled 90 per cent of the oil refined in the United States. By the time he retired at the age of 58, he was the country's wealthiest man. By the time he died, he had amassed the world's wealth.