Isaiah Hart platted and named the city of Jacksonville. 1817 - Amelia Island captured by U. S. to clear out pirates. Gen. Jackson crossed Florida border to punish Seminoles for their raids. Georgia legislator Cone argued to take in a portion of Florida including most of present Baker County. End of first Seminole War.
Settlers move in.
1820 - Florida formally became U. S. Territory. 1821 - All territory east of Suwannee organized as St. Johns County. First known Baptist church in Florida established on Pigeon Creek about 15 miles northeast of County. Alachua Trail crossed southeastern section of County. 1823 - Treaty of Moultrie Creek, near St. Augustine, removed Seminoles from north Florida.