6. Andrew Carnegie
Although better known representatives of the Rockefeller clan, the richest American of all time is the Andrew Carnegie, not the famous «oil kings».
Scottish immigrant in 1901, Carnegie sold his company to U.S. Steel for $ 480 million, or approximately a little more than 2.1% of US GDP at that time. In 2014, it would have amounted to $ 372 billion.
Andrew Carnegie (November 25, 1835 – August 11, 1919) was a Scottish American industrialist who led the enormous expansion of the American steel industry in the late 19th century. He is often identified as one of the richest people in history, alongside John D. Rockefeller and Jakob Fugger.
He built a leadership role as a philanthropist for the United States and the British Empire. During the last 18 years of his life, he gave away to charities, foundations, and universities about $350 million (in 2015 share of GDP, $78.6 billion) – almost 90 percent of his fortune. His 1889 article proclaiming «The Gospel of Wealth» called on the rich to use their wealth to improve society, and it stimulated a wave of philanthropy.