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.
Spanish Florida
Great Britain temporarily gained control of Florida beginning in 1763 as a result of the Anglo-Spanish War, but while Britain occupied the territory, it did not develop it further. Sparsely populated British Florida stayed loyal to the Crown during the American Revolutionary War, and by the terms of the Treaty of Paris which ended the war, the territory was returned to Spain in 1783. After a brief diplomatic border dispute with the fledgling United States, the countries set a territorial border and allowed Americans free navigation of the Mississippi River by the terms of Pinckney's Treaty in 1795.