John D. Rockefeller.

At age 16, John D. Rockefeller finished high school and began training as an accountant in Cleveland. He experienced class differences early, having been born on July 8, 1839, in Richford, New York, to Eliza Davison and William Rockefeller Sr. While still in school, he worked as a dishwasher and bellboy, meticulously keeping track of every penny. He later described money as frozen life. After completing his training in 1859, he ignored his employer’s pleas to stay and co-founded the brokerage Clark & Rockefeller Co. with Maurice Clark.

In 1859, Rockefeller founded Clark & Rockefeller Co., which soon secured contracts for oil drilling in Pennsylvania. In 1862, he brought in Samuel Andrews for his oil-refining patents, forming Andrews, Clark & Co. In 1865, after internal disputes, Rockefeller bought out his partners for $750,000, making him sole owner. He then founded Andrews & Rockefeller Co. In 1866, the company acquired two Cleveland refineries. By 1870, he launched Standard Oil Co., and within two years it controlled nearly all competition. Using third-party companies, he secretly bought refineries in Pittsburgh and Philadelphia, and by the late 1870s, Standard Oil refined 90% of American oil. To manage his empire, he created the Standard Oil Trust in 1882. The Sherman Antitrust Act of 1890 targeted his monopoly, but Rockefeller moved operations to New Jersey. In 1911, the Supreme Court ordered Standard Oil to split into 38 independent companies. He stepped back from management but retained control through investments until his death.

Rockefeller married Laura Celestia Spelman, known as Cettie, on September 8, 1864. They had four daughters and one son: John D. Rockefeller Jr., Elizabeth Rockefeller Strong, Alta Rockefeller Prentice, and Edith Rockefeller McCormick. A devout Baptist, he lived modestly and abstained from alcohol and tobacco his entire life. In 1901, he developed alopecia universalis, losing all body hair. He was a supporter of Abraham Lincoln.

Rockefeller’s impact on American industry and philanthropy is unparalleled. He founded the Rockefeller Institute for Medical Research in 1901 later Rockefeller University and the Rockefeller Foundation in 1913. His charitable efforts included building schools and hospitals. The breakup of Standard Oil led to modern antitrust enforcement. Adjusted for inflation, his peak net worth of approximately $340 billion makes him the richest person in history. His son, John D. Rockefeller Jr., completed Rockefeller Center in 1930, and his grandsons Nelson Rockefeller, David Rockefeller, and others became influential political and business leaders. He is most remembered as the architect of the modern oil industry and a foundational figure in American philanthropy.