Jackson County was created by the Florida Territorial Council in 1822 by splitting from Escambia County, making it the third county in the Territory. The county was named for Andrew Jackson, who had served as Florida's first military governor for six months in 1821. Jackson County originally spread from the Choctawhatchee River on the west to the Suwannee River on the east. The county had been shrunk close to its current boundaries by 1840 through the creation of new counties from its original land. Small changes to the county border continued through most of the 19th century, however.