September to November
Chattanooga was decisive in the fact that Tennesee was left in Union hands. The Confederates were commanded by Braxton Bragg, and the Union forces were first under William S. Rosecrans, then George H. Thomas, and finally Ulysses S. Grant. Rosecrans brilliantly maneuvered Bragg from Chattanooga in early September, but his Army of the Cumberland was met by reinforced Confederate forces and defeated in the Battle of Chickamauga on September 19th -20th. Bragg threw an incomplete siege around Chattanooga and detached troops to attack Knoxville. Grant, arriving at Chattanooga on October 23, reinforced the Army of the Cumberland, bringing it to 60,000 men. In the confused battles of Lookout Mountain and Missionary Ridge (Nov. 24-25, 1863), Thomas and Grant decisively defeated Bragg's 40,000 men.
Bibliography: Catton, Bruce, Grant Takes Command (1968); Connelly, Thomas L., Army of the Heartland (1967) and Autumn of Glory (1971); McDonough, J. L., Chattanooga (1984); McWhiney, Grady, Braxton Bragg and Confederate Defeat (1969).