Robber barons is a derogatory term used during America's Gilded Age (late 19th century) for wealthy industrialists who amassed their fortunes through ruthless business practices such as exploiting workers or manipulating markets.
Gilded Age: A period from around 1870-1900 characterized by rapid economic growth but also marked by severe social problems such as income inequality.
Trusts/Monopolies: Large corporations that control an entire industry or market. They can manipulate prices and stifle competition, similar to what many robber barons did.
John D. Rockefeller: An example of a "robber baron," he was an oil tycoon who used ruthless business tactics to establish a near-monopoly in the American petroleum industry.