The growth of industry and a wave of immigrants marked this period in American history. The production of iron and steel rose dramatically and western resources like lumber, gold, and silver increased the demand for improved transportation. Railroad development boomed as trains moved goods from the resource-rich West to the East. Steel and oil were in great demand. All this industry produced a lot of wealth for a number of businessmen like John D. Rockefeller (in oil) and Andrew Carnegie (in steel), known as robber barons (people who got rich through ruthless business deals). The Gilded Age gets its name from the many great fortunes created during this period and the way of life this wealth supported.
