Chattanooga, Tennessee, was a major rail center and a strategic vantage-point, with high ground competed-for by both sides. When Union forces were besieged in the town, General Ulysses S. Grant forced a supply-route, earning him Lincoln's particular gratitude.
Tennessee was the last state to join the Confederacy (June 1861), being deeply divided between the mountainous eastern zone, including Chattanooga, that was pro-Union, and the slave-intensive western counties that voted Confederate.[1] At one point, it was proposed that East Tennessee should become a separate state of the Union.[2]
When Tennessee seceded, future President Andrew Johnson was the only southern senator to remain in the senate,[3] putting his life at risk, but earning him credibility with Lincoln, who appointed him military governor of Tennessee in March 1862.[4] (The Confederacy retaliated by confiscating his land.)[5] As a southern War Democrat, Johnson was the natural choice as Lincoln's running-mate in his successful 1864 re-election bid.[6]
Tennessee contributed more regiments to the Union than any other Confederate state.[7][8]
As an important railroad hub, connecting major southern arsenals, Chattanooga was closely engaged in the Confederate war effort from the start, despite local resistance and even some guerrilla activity.[9] The city remained in Confederate hands until September 1863, after which it was occupied continuously by the Union. General Rosecrans retreated to safety there following his catastrophic defeat at Chickamauga, besieged by General Braxton Bragg until General Ulysses S. Grant was able to open a supply line. Grant drove the Confederates off Lookout Mountain, before routing them decisively at Missionary Ridge. Chattanooga then served as the gateway to Georgia for General William T. Sherman's 1864 campaign.
A raid by Union Brig. Gen. James Negley aimed at capturing the Rebel-held city. His long artillery bombardment provoked a disorganised response from enemy gunners, but Negley withdrew on the second day. It had been a minor Confederate victory, but it demonstrated that the Union could strike deep into the enemy heartlands.
Diversionary tactic by Union Maj. Gen. William S. Rosecrans to distract the attention of Confederate General Braxton Bragg through extensive shelling from the north-east of the city, while Union troops were massing to the south-west.[10] When Bragg learned of this, he retreated into Georgia, and the Union occupied the city.
After its shock-defeat at Chickamauga (Georgia), Rosecrans’ Army of the Cumberland retreated into its fortifications at Chattanooga, where it was under heavy siege by Bragg and facing surrender. The demoralised Rosecrans was urgently reinforced by the team of Grant, Thomas and Sherman.[11][12] Principal actions: