In many respects, the Creek War of 1813-1814 is considered part of the Southern Theater of the War of 1812. The Creek War grew out of a civil war that pitted Creek Indians striving to maintain their traditional culture, called Red Sticks, against those Creeks who sought to assimilate with United States society. Spurred by religious prophets and promises of British assistance, the Red Sticks grew increasingly aggressive and were eventually attacked by Mississippi Territory militia, which sparked the Creek War. With an almost complete dearth of Regular U.S. Army units, the militias from the Mississippi Territory, Tennessee, and Georgia, as well as Choctaw and Cherokee allies, all invaded the Creek Nation to attack the Red Stick Creeks. Initially the strikes were uncoordinated, but, despite abysmal supply systems, the U.S. forces eventually overwhelmed the Red Sticks. Their defeat at the Battle of Horseshoe Bend forced them into the treaty of Fort Jackson in August 1814, at which they ceded some 23 million acres in what are now the states of Alabama and Georgia.