Andrew Carnegie

Carnegie's family left Dunfermline for Pittsburgh in 1848, poor after his father's handloom weaving was undercut by mills. He started as a bobbin boy, became a telegraph messenger and then the protégé of a railroad boss, Thomas Scott, who gave him the inside track on investments. Carnegie Steel's efficiency built his fortune, and its merger into US Steel in 1901 created a company that still exists, though the 1892 Homestead strike remains a lasting stain.