United States territorial acquisitions
West Florida was declared to be a U.S. possession in 1810 by President James Madison after the territory had declared its independence from Spain. Madison ordered the U.S. Army to take control. Six weeks later, the army entered and occupied the capital, St. Francisville, putting an end to the republic after 74 days of independence. Spain did not relinquish its claim to sovereignty (see West Florida Controversy) until ratification of the Adams–Onís Treaty. General Andrew Jackson personally accepted the delivery of West Florida from its Spanish governor on July 17, 1821.
West Florida
On February 22, 1819, Spain and the United States signed the Adams-Onís Treaty. In this treaty Spain ceded both West and East Florida to the United States in exchange for compensation and the renunciation of American claims to Texas. Following ratification by Spain on October 24, 1820, and the United States on February 19, 1821, the treaty took effect, thereby establishing the current boundaries.