Seminole Wars (1817–18; 1835–42; 1855–58), three wars fought between the United States and the Seminole Indians in Florida. The wars led to the removal of all but a handful of Seminoles to Indian Territory (now Oklahoma).

The First Seminole War resulted from raids into Spanish-owned Florida by state militias seeking escaped slaves who had been given sanctuary by the Seminoles. The opening battle was fought in late 1817 when United States troops clashed with Seminoles who had staged retaliatory raids into the United States. In 1818 General Andrew Jackson was ordered by President Monroe to end the conflict. Jackson, however, exceeded his orders by launching a full-scale invasion of Florida, burning every Seminole village he and his troops could find. Jackson not only subdued the Indians but also seized several Spanish towns and executed two British subjects—Alexander Arbuthnot and Robert Ambrister—whom he had accused of inciting the Seminoles.

In spite of public protest in Great Britain, the British government took no action. Spain initially demanded return of its territory but then, realizing that Florida could not be defended, reluctantly ceded it to the United States in the Adams-Onís Treaty, ratified in 1821.

After the war the Seminoles were forced to sign three treaties, the first (1823) restricting them to a reservation in central Florida and the other two (1832 and 1833) providing for their removal to west of the Mississippi River. The majority of the Indians resisted resettlement. In 1835 a few hundred warriors under the leadership of Osceola began fighting a guerrilla-style action against United States troops. After Osceola was seized and imprisoned in 1837, a succession of generals, including Zachary Taylor, slowly subdued most of the Seminoles, and about 4,000 Seminoles were sent west. The cost of the war to the United States was some 1,500 soldiers killed and more than $20,000,000 expended.

Several hundred undefeated Seminoles fell far back into the swamplands of the Florida Everglades. During 1855–58 a third war was fought, mainly a series of small engagements. The Seminoles were subdued, and all but about 125 then agreed to be removed to Indian Territory. Descendants of those that remained live in the Everglades today.