Chickamauga, Battle of, September 1920, 1863, an engagement in the American Civil War. It was fought near Chickamauga Creek, a small stream about 12 miles (19 km) east of Chattanooga, Tennessee. General William S. Rosecrans, the Union commander, had maneuvered a smaller Confederate force under General Braxton Bragg out of Chattanooga and pursued it into northern Georgia. Bragg, reinforced by General James Longstreet, attacked and in a confused battle broke through the Union lines. The corps of General George H. Thomas held fast until night, covering the retreat of the Union army to Chattanooga. For this stand, Thomas was called The Rock of Chickamauga. The Union army remained penned up in Chattanooga until General U. S. Grant arrived with reinforcements.

Union soldiersUnion soldiers engage Confederate troops at the battle of Chickamauga.

About 66,000 Confederates and 58,000 Union soldiers were in the battle. The Confederates lost 17,800 killed, wounded, and missing; the Union forces, 16,179. The battlefield is a part of Chickamauga and Chattanooga National Military Park.