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
The area known as West Florida was originally claimed by Spain as part of "La Florida", which included most of what is now the southeastern United States. Spain made several attempts to conquer and colonize the area, notably including Tristán de Luna's short-lived settlement in 1559, but it was not settled permanently until the 17th century, with the establishment of missions to the Apalachee. In 1698 the settlement of Pensacola was established to check French expansion into the area.