After Union General William Rosecrans’ defeat at Chickamauga on September 18–20, 1863, the Army of the Cumberland fell back to the high ground, and rail hub, at Chattanooga Tennessee. Confederate General Braxton Bragg chose to besiege the Union forces entrenched around the city, hoping to starve them into surrender.
In October, Ulysses S. Grant was given command of all Union forces in the west and replaced Rosecrans with General George Thomas. After securing the vital “Cracker Line” to feed the starving army, and defeating the Confederate counterattack at Wauhatchie, Grant turned his focus to a Union breakout.
On November 23, the Union swept Confederate defenders off Orchard Knob. The next day, General Joseph Hooker captured Lookout Mountain in the “Battle Above the Clouds.”
On November 25, Grant ordered a double envelopment: General Sherman would assault Missionary Ridge from the north, while Hooker attacked from the south. George Thomas was to advance in the center once both flanks had been engaged. The flank attacks stalled but Thomas’ men quickly swept the Confederates out of their defense at the base of the ridge and continued, without orders, up the slope. Although disorganized, the Union assault up the ridge shattered the Confederate defenses.
What followed was a running retreat and pursuit. Grant’s pursuit was effectively stopped on November 27 at Ringgold Gap where Confederate General Patrick Cleburne surprised and stopped Hooker’s larger force. After Cleburne’s stunning defense, which allowed the Confederate wagons and artillery to pass through the gap unharmed, Grant abandoned his pursuit.