Florida
Florida had become a burden to Spain, which could not afford to send settlers or garrisons. Madrid therefore decided to cede the territory to the United States through the Adams–Onís Treaty, which took effect in 1821. President James Monroe was authorized on March 3, 1821 to take possession of East Florida and West Florida for the United States and provide for initial governance. Andrew Jackson, on behalf of the U.S. federal government, served as a military commissioner with the powers of governor of the newly acquired territory for a brief period. On March 30, 1822, the U.S. Congress merged East Florida and part of West Florida into the Florida Territory.
By the early 1800s, Indian removal was a significant issue throughout the southeastern U.S. and also in Florida. In 1830, the U.S. Congress passed the Indian Removal Act and as settlement increased, pressure grew on the U.S. government to remove the Indians from Florida. Seminoles offered sanctuary to blacks, and these became known as the Black Seminoles, and clashes between whites and Indians grew with the influx of new settlers. In 1832, the Treaty of Payne's Landing promised to the Seminoles lands west of the Mississippi River if they agreed to leave Florida. Many Seminole left at this time.
Kiln, Mississippi
In 1763, France ceded Louisiana east of the Mississippi River to Great Britain in the Treaty of Paris. The area became part of the colony of British West Florida. In 1783, British West Florida was ceded to Spain as part of the Peace of Paris, and the area became part of the province of Spanish West Florida. The United States claimed West Florida in 1803 as part of the Louisiana Purchase. However, Spain disputed this claim. Tensions between the United States and Spain grew as many Americans began to move into the area. A large number of these immigrants were Tories who resented Spanish rule. On May 14, 1812, immediately prior to the start of the War of 1812 with Great Britain, with whom Spain was allied, the United States assigned the claimed area to the Mississippi Territory, even though the area was still governed by Spain. On February 12, 1813, the United States Congress passed a statute giving President James Madison authority to occupy the area. In April 1813, an American force occupied Mobile and received the surrender of the Spanish commander.