From Ohio History Central
The Battle of Chattanooga took place from November 23 to November 25, 1863, during the American Civil War.
The battle resulted from the defeat of the Union's Army of the Cumberland, commanded by General William Rosecrans of Ohio, at the Battle of Chickamauga. Following Chickamauga, the Army of the Cumberland regrouped at Chattanooga. The Army of Tennessee, under the command of Braxton Bragg, seized the heights, including Missionary Ridge and Lookout Mountain, surrounding the city. Southern artillery prevented supply trains or reinforcements from reaching Rosecrans's army and prevented the Northerners from retreating. The Northern soldiers were in a dire situation. They had to surrender, starve, or attack a larger, well-fortified force.