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.
Seminole Wars
Spain ceded Florida to the United States in 1819 with the Adams–Onís Treaty, and the United States took possession in 1821. Effective government was slow in coming to Florida. General Andrew Jackson was appointed military governor in March 1821, but he did not arrive in Pensacola until July. He resigned the post in September and returned home in October, having spent just three months in Florida. His successor, William P. Duval, was not appointed until April 1822, and he left for an extended visit to his home in Kentucky before the end of the year. Other official positions in the territory had similar turn-over and absences.