How was James Buchanan duke a robber baron?

James Buchanan Duke was considered a robber baron primarily for his role in the tobacco industry, where he established the American Tobacco Company, effectively monopolizing cigarette production and distribution. His aggressive business practices, including the use of underhanded tactics to eliminate competition, exemplified the era's ruthless capitalism. Additionally, he expanded his influence through significant investments in hydroelectric power and the creation of Duke Energy, further solidifying his control over multiple industries. His legacy is marked by both his wealth accumulation and the contentious methods he employed to achieve it.