There are 3 US Post Offices in Perry County serving a total of 11,394 residents equating to 3,798 residents per post office. It's estimated that approximately 18,186 packages are handled across the 3 county post offices annually. Perry County is a county located in the U.S. state of Mississippi. As of the 2010 census, the population was 12,250. The county seat is New Augusta. The county is named after the War of 1812 naval hero, Oliver Hazard Perry. Perry County is part of the Hattiesburg, MS Metropolitan Statistical Area. Until 1906, the county seat was the old town of Augusta, near the center of the county on the east bank of the Leaf River. At Old Augusta, the outlaw James Copeland was executed by hanging on October 30, 1857. Old Augusta remains a small village today. New Augusta, two miles south of Old Augusta, was made the county seat of Perry County, because it was situated on the Mobile, Jackson & Kansas City Railroad.