He then moved rapidly through a succession of jobs with Western Union and the Pennsylvania Railroad. In 1865, he resigned to establish his own business enterprises and eventually organized the Carnegie Steel Company, which launched the steel industry in Pittsburgh. Andrew Carnegie ultimately made his fortune in steel, changing the industrial world in the process. He introduced the Bessemer steel making process to America. Because Carnegie owned the iron-ore deposits that furnished the raw materials for steelmaking, as well as the ships and railroads that transported these supplies to his mills he was able to run his company with greater efficiency, it was a process called vertical integration. This enabled the company to achieve greater efficiencies than any other manufacturing industry of the time.
By the time of his death in 1919, Andrew Carnegie had given away over $350 million to provide more than 2,500 free public libraries throughout the world.