American businessman Andrew William Mellon (1855-1937) crowned a highly successful entrepreneurial career with over a decade of service as U.S. secretary of the Treasury.

Andrew Mellon was born on March 24, 1855, in Pittsburgh, Pa. Unlike most members of the industrial elite of his generation, Mellon attended college, although he withdrew shortly before graduation.

In 1882 Mellon became the owner and manager of the family banking firm, T. Mellon & Sons. A few years later he provided financial assistance for the enterprise which would become the Aluminum Company of America, and this concern was controlled by the Mellon family. He began to invest in the oil industry in the 1890s and was one of those who organized the Gulf Oil Corporation in 1901. Mellon invested in a variety of other industrial firms and became a director of many of them. In 1902, when the family private banking house was converted into a commercial...