Which U.S. president issued the 1803 Louisiana Purchase agreement with France?

President Thomas Jefferson’s administration issued the 1803 Louisiana Purchase agreement with France.

Jefferson authorized diplomats Robert Livingston and James Monroe to negotiate with France. Their original goal was to secure access to New Orleans and perhaps purchase nearby territory. Napoleon Bonaparte’s government unexpectedly offered the entire Louisiana Territory, and the American negotiators accepted the opportunity after consulting Jefferson.

The purchase raised constitutional questions because the Constitution did not explicitly describe a presidential power to acquire new territory. Jefferson personally favored a strict reading of the Constitution, but he concluded that the agreement was too important to reject. The Senate ratified the treaty in October 1803, and the United States formally took possession in December.

James Madison was Jefferson’s secretary of state and helped manage the diplomacy, but he was not president until 1809. The agreement therefore belongs to Jefferson’s presidency, even though several officials contributed to completing it.