That said, the rags-to-riches magnate was seemingly sympathetic to workers' rights, and later admitted to regretting his implicit support of Frick's suppression of the industrial action.

Carnegie sold his steel business to J. P. Morgan in 1901 and then devoted himself entirely to philanthropy. By the time he died in 1919, the deep-pocketed tycoon had given away most of his fortune, which was worth around $375 billion in today's money. His generous donations founded and funded libraries, museums, universities, and peace organizations.

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