Edgar Thomson Steel Works 1873

Andrew Carnegie was the epitome of the American rags-to-riches dream. Arriving in America at 13, the son of a migrant Scottish handloom weaver, by his late 30s he had already amassed a fortune from oil and railroads, before deciding to move into the steel industry. His first plant was named for his mentor (and prime customer), J. Edgar Thomson, another self-made industrialist and president of Pennsylvania Railroads. Carnegie would go on to revolutionize the industry through the application and refinement of the Bessemer process for producing steel from pig-iron. His application of the principles of vertical integration was even more pioneering, achieving control or ownership of all the raw materials necessary for steel production, plus a near monopoly of many steel manufactures, such as railway sleepers. Carnegie became a legendary philanthropist in his retirement, but was less benevolent with striking workers: ten were killed by strike-breakers in the ruthless suppression of a 1892 dispute.