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.
Republic of West Florida
The United States did not recognize the independence of the Republic of West Florida, and on October 27, 1810, President James Madison of it, on the basis that it was part of the Louisiana Purchase. In his proclamation, Madison invoked the portion of the Louisiana Purchase agreement that directly quoted the 1800 St. Ildefonso treaty between France and Spain: Louisiana, Madison stated, had "the same extent that it had in the hands of Spain, and that it had when France originally possessed it." However, neither the 1800 treaty nor the 1803 purchase includes the word "originally"; instead, they state, "with the same extent that it now has in the hands of Spain and that it had when France possessed it." Madison's tweak served his annexation rationale but had no basis in the treaty language.