McAlester is a city in and county seat of Pittsburg County, Oklahoma, United States. The population was 18,363 at the 2010 census, a 3.4 percent increase from 17,783 at the 2000 census, making it the largest city in the former Choctaw Nation of Oklahoma, followed by Durant. The town gets its name from J.J. McAlester, an early white settler and businessman, who later became Lieutenant Governor of Oklahoma. McAlester married Rebecca Burney, daughter of a full-blood Chickasaw family, which made him a citizen of the Chickasaw Nation.McAlester is the home of the Oklahoma State Penitentiary, site of an "inside the walls" prison rodeo from which ESPN's SportsCenter once broadcast. Oklahomans sometimes refer to the state prison simply as "Big Mac" or "McAlester".McAlester is home to many of the employees of the McAlester Army Ammunition Plant. This facility makes essentially all of the bombs used by the United States military.