Perry County is a county in the Commonwealth of Pennsylvania. As of the 2020 census, the population was 45,842. The county seat is New Bloomfield. The county was created on March 22, 1820, and was named for Oliver Hazard Perry, a hero of the War of 1812, who had recently died. It was originally part of Cumberland County and was created in part because residents did not want to travel over the mountain to Carlisle, the county seat of Cumberland County. Landisburg became the temporary county seat before New Bloomfield was ultimately chosen. The county is part of the South Central Pennsylvania region of the state.

The Harrisburg–York–Lebanon, PA combined statistical area (CSA) is a region assigned by the U.S. Office of Management Budget that includes six cities in the Harrisburg and York areas along with several metropolitan statistical areas of Pennsylvania that combine to form a combined statistical area. As of the 2010 United States census, the CSA had a population total of 1,219,422, and ranked the third most populous CSA in Pennsylvania and 43rd most populous in the nation.