Frederick is a city and county seat of Tillman County, Oklahoma, United States. Once titled "The Friendly City", its charm and receptiveness leaves visitors feeling like locals. The population was 3,940 at the 2010 census. It is an agriculture-based community that primarily produces wheat, cotton, and cattle. Frederick is home to three dairies, a 1400-acre industrial park, and Frederick Regional Airport, which includes restored WWII hangars which house the WWII Airborne Demonstration Team.