One of the significant legacies of the Gilded Age was the economic transformation it brought about. The rise of industries like steel, oil, and railroads during this period revolutionized the American economy. Industrial tycoons, known as Robber Barons, such as Andrew Carnegie and John D. Rockefeller, accumulated vast fortunes through their dominance in these industries. Their wealth and success laid the foundation for the modern capitalist system we see today.