The history of U.S. foreign policy from 1801 to 1829 concerns the foreign policy of the United States during the presidential administrations of Thomas Jefferson, James Madison, James Monroe, and John Quincy Adams. International affairs in the first half of this period were dominated by the Napoleonic Wars, which the United States became involved with in various ways, including the War of 1812. The period saw the United States double in size, gaining control of Florida and lands between the Mississippi River and the Rocky Mountains. The period began with the First inauguration of Thomas Jefferson in 1801. The First inauguration of Andrew Jackson in 1829 marked the start of the next period in U.S. foreign policy.