http://en.wikipedia.org/wiki/Seminole_Wars (for complete description)
The Seminole Wars, also known as the Florida Wars, were three conflicts in Florida between various groups of native Americans, collectively known as Seminoles, their allies, and the United States Army. The First Seminole War was from 1817 to 1818, the Second Seminole War from 1835 to 1842, and the Third Seminole War from 1855 to 1858. The first conflict with the Seminoles arose out of tension relating to Andrew Jackson's attack on Negro Fort in 1816. Jackson also attacked the Spanish at Pensacola which ultimately resulted in a cession of the colony to United States rule.