Andrew Carnegie led the expansion of the American steel industry in the late 19th century and is often identified as one of the richest Americans ever. 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.

Carnegie was born in Dunfermline, Scotland, and emigrated in 1848 to the United States with his parents. Carnegie started work as a telegrapher and by the 1860s had investments in railroads, railroad sleeping cars, bridges and oil derricks. He accumulated further wealth as a bond salesman raising money for American enterprise in Europe. He built Pittsburgh's Carnegie Steel Company, which he sold to J.P. Morgan in 1901 for $480 million. It became the U.S. Steel Corporation. After selling Carnegie Steel, he surpassed John D. Rockefeller as the richest American for the next couple of years.

Carnegie devoted the remainder of his life to large-scale philanthropy, with special emphasis on local libraries, world peace, education and scientific research.

In 1849, Carnegie became a telegraph messenger boy in the Pittsburgh Office of the Ohio Telegraph Company, at $2.50 per week (or $76 in 2017 dollars), following the recommendation of his uncle. He was a very hard worker and would memorize all of the locations of Pittsburgh's businesses and the faces of important men. He made many connections this way. He also paid close attention to his work, and quickly learned to distinguish the differing sounds the incoming telegraph signals produced. He developed the ability to translate signals by ear, without using the paper slip, and within a year was promoted to operator. Carnegie's education and passion for reading was given a great boost by Colonel James Anderson, who opened his personal library of 400 volumes to working boys each Saturday night. Carnegie was a consistent borrower and a "self-made man" in both his economic development and his intellectual and cultural development.

Carnegie died[58] on August 11, 1919, in Lenox, Massachusetts at his Shadow Brook estate, of bronchial pneumonia.[59] He had already given away $350,695,653 (approximately $76.9 billion, adjusted to 2015 share of GDP figures)[60] of his wealth. After his death, his last $30,000,000 was given to foundations, charities, and to pensioners.[61] He was buried at the Sleepy Hollow Cemetery in North Tarrytown, New York. The grave site is located on the Arcadia Hebron plot of land at the corner of Summit Avenue and Dingle Road. Carnegie is buried only a few yards away from union organizer Samuel Gompers, another important figure of industry in the Gilded Age