Florence (O'odham: S-auppag) is a town, 61 miles (98 km) southeast of Phoenix, in Pinal County, Arizona, United States. Florence, which is the county seat of Pinal County, is one of the oldest towns in that county and is regarded as a National Historic District with over 25 buildings listed on the National Register of Historic Places. The population of Florence was 25,536 at the 2010 census.
The area where the current town of Florence is located was once inhabited by the Hohokam, ancestors of the O'odham people. Prior to the establishment of the town, the Gila River served as a part of the border between the United States and Mexico. In 1853, the Gadsden Purchase extended American territory well south of the Gila.
Levi Ruggles, a veteran of the American Civil War, founded the town of Florence on the south bank of the Gila River. He came to Arizona Territory in 1866 as a U.S. Indian Agent. Recognizing the agricultural potential of the valley, he found an easily fordable crossing on the Gila River and surveyed a townsite there. With the aid of Governor R.C. McCormick, he secured a post office in August of the same year. Ruggles held numerous public offices including that of Territorial Legislator. Florence became the county seat in the newly formed Pinal County.