John D. Rockefeller
John Davison Rockefeller (July 8, 1839 – May 23, 1937) was an American businessman. He controlled an oil company called Standard Oil, which sold most of the oil in the United States in the late 19th and early 20th centuries. He was the first billionaire in world history. He is considered to be the richest man in American history, and one of the richest men in the history of the world. 
Today, the money he made would be worth more than half a trillion dollars. He used the large amounts of money he had to do various things, including starting the University of Chicago, funding important medical research, and giving the land for the General Assembly Building of the United Nations.