Which individual created a monopoly over the banking industry?

J.P. Morgan played a pivotal role in shaping the American banking industry during the late 19th and early 20th centuries. He is best known for consolidating companies and securing the financial interests of large corporations, which led to significant control over the banking sector. Morgan's firm was instrumental in financing and restructuring major American industries, including railroads and steel, allowing him to influence market conditions and operations widely. His ability to coordinate investments and form powerful financial alliances is what effectively placed him in a position of monopoly within the banking industry.

In contrast, Cornelius Vanderbilt primarily made his fortune in railroads and shipping, while John D. Rockefeller was known for his dominance in the oil industry with Standard Oil. Andrew Carnegie focused on steel production and was a major figure in the steel industry, but none of these individuals had the same controlling influence over the banking sector as J.P. Morgan did.