William Pope Duval was the first civilian governor of the Florida Territory, succeeding Andrew Jackson, who had been a military governor. In his twelve-year governorship, from 1822 to 1834, he divided Florida into four territories, established the local court system, and chose Tallahassee as the territory's capital because of its central location. Duval County, where Jacksonville is located, Duval Street in Key West, and Duval Street in Tallahassee are named for him.

Duval County is in the northeastern part of the U.S. state of Florida. As of July 2022, the population was 1,016,536, up from 864,263 in 2010. It is Florida's sixth-most populous county. Its county seat is Jacksonville, with which the Duval County government has been consolidated since 1968. Duval County was established in 1822, and is named for William Pope Duval, Governor of Florida Territory from 1822 to 1834. Duval County is the central county of the Jacksonville Metropolitan Statistical Area.