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 Controversy
In 1810, a group of discontented American and British settlers in the area of Baton Rouge learned that the Spanish colonial governor, who had feigned sympathy, was in fact mounting a force against them. They revolted by overrunning a Spanish garrison at Fort San Carlos in Baton Rouge on September 23, 1810, and declared the independence of the Republic of West Florida on September 26. On October 27, the United States president proclaimed that the territory should be annexed, and Spain, then embroiled in the Peninsular War with France, could do little to resist. On December 10, the United States military completed the forcible occupation and acquiescence of the Republic of West Florida.