Here’s some additional information about Chickamauga Battlefield which is located south of Chattanooga, Tennessee and just over the border into Georgia. The prize being fought for was Chattanooga and the rail center and gateway to the heart of the Confederacy.
The fighting began shortly after dawn on September 19th near Jay’s Mill, bringing on a general battle that spread south for nearly four miles. The armies fought desperately all day, often hand-to-hand, and gradually the Confederates pushed the Federals back. When Rosecrans shifted some troops to meet the attacks, a gap opened briefly in the Federal line allowing Longstreet’s Confederates to assault at that point, routing Rosecrans and half his army. Although some rallied and formed a new battleline on Snodgrass Hill, holding their ground against repeated assaults, they eventually retreated to Chattanooga.
The authorities in Washington soon became aware of the problem and sent Maj. Gen. Joseph Hooker from Virginia with 20,000 men in October and Maj. Gen. William T. Sherman from Mississippi with 16,000 in mid-November. Maj. Gen. George H. Thomas replaced Rosecrans as head of the Army of the Cumberland and Maj. Ulysses S. Grant assumed overall command after which the situation began to change. A shorter supply route was opened, and on November 24th during a heavy fog, Hooker’s soldiers pushed the Confederates out of their defenses, and on November 25th Grant launched Sherman’s troops against the Confederates eventually causing them to retreat into Georgia. Union armies now controlled the city of Chattanooga and nearly all of Tennessee and with Chattanooga as his base Sherman started his march to Atlanta and the sea.
Chickamauga was one of the bloodiest battles of the Civil War. Confederate losses totaled more than 18,000 out of some 66,000 engaged; Federal losses were 16,000 out of 58,000.
The map below gives you a good idea of the scope of this action. The Lookout Mountain, MIssionary Ridge and Chickamauga Battles were fought just a few miles from one another and according to the military record Andrew Boss was present at these battles.
SOURCE:National Park Service, U.S. Department of the Interior. Chickamauga and Chattanooga Official Map and Guide to National Military Park, Georgia/Tennessee.