Maritime history of Florida
Spain ceded Florida to the United States as part of the Adams–Onís Treaty of 1819, and Florida became a U.S. territory in 1821. Coastal trade with other markets continued to expand and towns like Jacksonville, Pensacola and Tampa became important ports. After becoming a U.S. territory, the federal government began building a series of lighthouses as aids to navigation along the coasts of Florida to mark dangerous headlands, shoals, bars and reefs.
Treaty of Moultrie Creek
The indigenous peoples of Florida had largely died out by early in the 18th century, and various groups and bands of Muskogean-speakers (commonly called "Creek Indians") and other groups such as Yamasee and Yuchi moved into the area, often with the encouragement of the Spanish colonial government. These groups, which often lived on both sides of the border between Florida and Georgia, came into increasing conflict with white settlers after the United States became independent. When the United States acquired Florida from Spain in 1821 (by means of the Adams-Onís Treaty), the conflict increased. In 1823, the United States government decided to settle the Seminoles on a reservation in the central part of the territory.