How did the usa gain the territory of florida

American settlers moved in and began to resist Spanish control. After years of border arguments, Spain finally agreed to cede the Florida Territory to the U.S. in 1819 by signing the Adams-Onis Treaty, signed by Spanish minister Luis De Otis and U.S. Secretary of State John Quincy Adams. More settlers arrived and Tallahassee became the capital. Florida was admitted to the Union in 1845. 

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