Utsunomiya became part of the US puppet state South Japan after World War II. It was the site of a pitched battle between the invading North Japanese Army and the United States Army. The U.S. Army able to stop North Japan's momentum, and begin pushing them back eventually to Sendai north of the old demilitarized zone along the Agano River. Sgt. Mike Sullivan's company was part of the American forces stopping the North Japanese advance at Utsunomiya.