The Charleston riot occurred on March 28, 1864, in Charleston, Illinois, after Union soldiers and local Republicans clashed with local insurgents known as Copperheads. By the time the riot had subsided, nine were dead and twelve had been wounded. It is generally thought that one of the events that triggered the riot was the treatment of Judge Charles H. Constable by Union soldiers. The soldiers humiliated Constable by making him swear allegiance to the federal government, due to his decision to allow four Union deserters to go free in Marshall, Illinois. When the riot began, Judge Constable was holding court in Charleston.