Which U.S. financier's rescue efforts helped end the Panic of 1907?

J. P. Morgan's rescue efforts helped end the Panic of 1907.

The panic began after a failed attempt to corner the stock of United Copper Company. When the associated trust companies suffered runs, depositors and banks rapidly lost confidence. The crisis worsened because the United States lacked a central bank able to act as a lender of last resort.

J. P. Morgan convened bankers in New York, examined institutions' assets, arranged loans, and pressured financial leaders to provide support. His group helped stabilize the Knickerbocker Trust Company's surrounding banking network and later assisted the New York City government with emergency financing. Morgan's role made him the central private figure in the rescue.

The panic exposed weaknesses in the U.S. financial system. It contributed to political support for monetary reform and ultimately helped lead to the creation of the Federal Reserve System in 1913. Morgan did not single-handedly solve every problem, and the Treasury Department and other bankers also supplied important assistance.