Prelude to the Battle
Battle of Stones River
On December 26, 1862, Major General William S. Rosecrans led the Union Army of the Cumberland out of Nashville, Tennessee, with orders to capture Chattanooga, Tennessee. Chattanooga was an important railroad junction that connected the upper Confederacy with the Deep South. Between Rosecrans and Chattanooga was Lieutenant General Braxton Bragg and the Confederate Army of Tennessee.
On December 31, the two armies clashed at the Battle of Stones River near Murfreesboro, Tennessee, which lasted until January 2, 1863. The Union army prevailed, and Bragg retreated south towards Tullahoma, Tennessee. In June, the Federals moved on the Confederates at Tullahoma, forcing Bragg to withdraw his army to Chattanooga.
Bragg Abandons Chattanooga
In mid-August, Rosecrans prepared to assault Chattanooga, but a series of maneuvers on his part convinced Bragg that the city was indefensible. On September 9, Bragg abandoned Chattanooga and led the Army of Tennessee through the mountains into northern Georgia. Although Rosecrans had achieved his aim of capturing Chattanooga, he pursued Bragg’s army into Georgia.
Battle of Chickamauga
Stung by criticism that he received for abandoning Chattanooga, Bragg resolved to win the city back. On September 19, the Army of Tennessee attacked the Union Army of the Cumberland at the Battle of Chickamauga (September 19–20, 1863). Bragg’s army drove the Federals back toward Chattanooga, forcing them to occupy the defensive works previously constructed by the Confederates. Bragg seized the high ground overlooking Chattanooga (Lookout Mountain, Seminary Ridge, and Raccoon Mountain) and laid siege to the city.
Because of the Army of the Cumberland’s dire situation, Northern authorities sent 20,000 soldiers under the command of General Joseph Hooker, and 16,000 men that General William T. Sherman led, to assist the Army of the Cumberland. Officials placed General Ulysses S. Grant in command of all Northern soldiers near Chattanooga and also replaced Rosecrans with General George H. Thomas as the commander of the Army of the Cumberland.
The Cracker Line
After some reinforcements arrived in late October 1863, Grant immediately embarked upon a plan to relieve the supply problems of the Army of the Cumberland. By October 28, Grant’s men opened a narrow supply line that became known as the “Cracker Line.” Brigadier General William F. Smith had originally proposed the line, but Rosecrans did not act on his subordinate’s recommendation. When Grant arrived in Chattanooga, he endorsed Smith’s plan. Because Confederate forces did not offer much resistance to the work crews creating the new route, the operation was a success.
Battle of Wauhatchie
Under orders from Braxton Bragg, Confederate Lieutenant General James Longstreet launched at night attack against Major General Joseph Hooker’s forces at Wauhatchie, Tennessee, on October 28, 1863. Longstreet sent in far fewer men against the Union position than Bragg had ordered. Despite Hooker’s confused response, the Federals held their position during the assault that lasted until early the next morning. Longstreet’s failure to dislodge Hooker at the Battle of Wauhatchie prompted Bragg to dispatch Longstreet and his men to eastern Tennessee to deal with Major General Ambrose E. Burnside and his Army of the Ohio, which had recently occupied Knoxville. Bragg’s decision to send away Longstreet’s corps markedly weakened his army near Chattanooga.
Battle of Chattanooga
Following the opening of the Cracker Line and the Battle of Wauhatchie, Grant began planning an assault on the Confederate forces. He intended to wait until Sherman’s men arrived on the battlefield. The vanguard of Sherman’s men began to arrive at Chattanooga on November 20, 1863. Three days later, rumors circulated through Northern lines that the Confederate forces were retreating. Grant ordered General Thomas to reconnoiter the center of the Confederate line at the base of Missionary Ridge. Early in the afternoon, 14,000 Northern forces under Brigadier-General Thomas J. Wood easily overpowered the Confederates at Orchard Knob. Initially, Grant had ordered the men to return to Northern lines, but upon seeing the ease the Union men had in securing the position, he ordered his soldiers to hold the position and to entrench.
Union forces continued their assault on the Confederate position the next day. On November 24, General Hooker’s men attacked Confederate forces on Lookout Mountain on the Southerners’ left flank. By mid-afternoon the Union assault had stalled, primarily because of a thick fog that enveloped the mountain, prompting soldiers to nickname the Battle of Lookout Mountain as the Battle Above the Clouds. Although Hooker’s men did not take the mountain, he correctly predicted that Southern forces would withdraw that night.
After abandoning Lookout Mountain, Bragg concentrated his Confederate soldiers on Missionary Ridge. On November 25, Grant ordered an assault on Bragg’s new position. Grant directed Sherman, who still did not have his entire force on the battlefield, to attack the Confederate right flank. Grant ordered Hooker to demonstrate against Bragg’s left flank but to avoid a determined assault.
Following Grant’s instructions, Hooker slowly pushed the Confederate forces in front of him north along Missionary Ridge. Grant ordered General Thomas, who led the Northern troops across from the center of the Confederate line to assist Sherman with his assault. Unfortunately for Grant, stiff Confederate resistance slowed Sherman’s.
Late in the afternoon, Grant directed Thomas to assault the center of the Confederate line, but he only wanted the Federals to capture the Southern rifle pits at the bottom of Missionary Ridge. Thomas’ Army of the Cumberland advanced, seized the rifle pits, and then proceeded, against their original orders, to drive the Confederates from Missionary Ridge. Bragg’s army retreated from the ridge, ending the Battle of Missionary Ridge and the Battle of Chattanooga.
Outcome of the Battle
The Union victory at the Battle of Chattanooga drove the Confederate Army of Tennessee into Georgia and paved the way for William T. Sherman’s Atlanta Campaign. Union casualties totaled 5,815 (killed, wounded, captured/missing). The Confederacy lost 6,670 men (killed, wounded, captured/missing).