John Davison Rockefeller Sr. (July 8, 1839 – May 23, 1937) was an American businessman and philanthropist. He was one of the wealthiest Americans of all time and one of the richest persons in modern history. Rockefeller was born into a large family in Upstate New York who moved several times before eventually settling in Cleveland, Ohio. He became an assistant bookkeeper at age 16 and went into several business partnerships beginning at age 20, concentrating his business on oil refining. Rockefeller founded the Standard Oil Company in 1870. He ran it until 1897 and remained its largest shareholder. In his retirement, he focused his energy and wealth on philanthropy, especially regarding education, medicine, higher education, and modernizing the Southern United States.
Rockefeller's wealth grew substantially as kerosene and gasoline became increasingly important commodities, eventually making him the richest person in the United States. By 1900, Standard Oil controlled about 90% of the nation's oil production. The company lowered production costs and expanded oil distribution through corporate and technological innovations, but it also benefited from a legal environment that enabled consolidation. Critics argue that regulatory capture played a role in facilitating its monopoly power–a view reinforced by Rockefeller's reputed remark, "Competition is a sin."