After 1857 he lived in Seattle, WA, where he had begun to work as a bookkeeper in 1855. In 1858 he went into the produce commission business. His firm, Clark & Rockefeller, invested in an oil refinery in 1862, and in 1865 Rockefeller sold out his share to his partner Clark, paid $72,500 for a larger share in another refinery, and formed the partnership of Rockefeller & Andrews.
At about the same time Rockefeller's brother, William, started another refinery. In 1867 Rockefeller & Andrews absorbed this business, and Henry M. Flagler joined the partnership. In 1870 the two Rockefellers, Flagler, Andrews and a refiner named Stephen V. Harkness formed the Standard Oil Company, with John D. Rockefeller as president.
In the early 1870s, Charles Pratt and Henry H. Rogers, two of the early pioneers of the emerging U.S. petroleum industry, became involved in conflicts with Rockefeller's infamous South Improvement Company, which was basically a scheme to obtain favorable net rates from the Pennsylvania Railroad (PRR) and other railroads through a secret system of rebates. Rockefeller and the South Improvement Company scheme outraged independent oil producers in western Pennsylvania and refineries there and afar alike.
The opposition to the South Improvement Company scheme among the New York refiners was led by Rogers. The New York interests formed an association, and about the middle of March, 1872, sent a committee of three, with Rogers, of Charles Pratt and Company, as head, to Oil City to consult with the Oil Producers' Union there. Their arrival in the oil regions was a matter of great satisfaction. Working with the Pennsylvania independents, they managed to forge an agreement with the PRR and other railroads whose leaders eventually agreed to open rates to all and promised to end their shady dealings with South Improvement. The oil men were most exultant, but their joy was to be short-lived, for Rockefeller had already begun forming his Standard Oil organization and was busy trying another approach, which included frequently buying-up opposing interests.
Rockefeller approached Charles Pratt with his plans of cooperation and consolidation. Pratt talked it over with Rogers, and they decided that the combination would benefit them. Rogers formulated terms, which guaranteed financial security and jobs for Pratt and himself. John D. Rockefeller quietly accepted the offer on Rogers' exact terms. Charles Pratt and Company (including Astral Oil) became one of the important formerly independent refiners to join Rockefeller's organization in 1874. Pratt's son, Charles Millard Pratt (1858-1913) became Secretary of Standard Oil. Henry H. Rogers became one of Rockefeller's key men.
Standard Oil gradually gained virtual control of oil production in America. Its business methods, which brought immense wealth to the ownership and lower prices for consumers, were widely and severely criticized. Its growth increased further in 1882, when separate companies were organized in each state; and in later years, as the first great American trust, the Standard Oil Company was hotly attacked during the anti-trust movement, especially after the publication of the 1904 book The History of the Standard Oil Company, by Ida Tarbell, whose father had been driven out of business by Rockefeller's business arrangement with the South Improvement Company. Standard Oil's economies of scale lowered the cost of oil based products so that almost everyone could afford them.