Who were the monopolies and trusts supported by?

Monopolies and trusts in the late 19th and early 20th centuries were often supported by wealthy industrialists and businessmen, such as John D. Rockefeller in oil, Andrew Carnegie in steel, and J.P. Morgan in finance. They leveraged political influence, lobbied for favorable legislation, and sometimes engaged in corrupt practices to maintain their dominance. Additionally, these entities often relied on a network of political allies and government officials who benefited from their economic power. This combination of financial resources and political connections allowed them to stifle competition and secure their market positions.