Siege of Chattanooga

After defeating Rosecrans's Union army at the Battle of Chickamauga, Bragg's Confederates received intelligence that their foes were in full retreat, but they did not mount an aggressive pursuit. Bragg did not want to leave the railroad, which was serving as his supply line. The cavalry under Nathan Bedford Forest moved to within three miles of Chattanooga, where the Federals had positioned themselves. The placed could have been easily captured, but Bragg would not move. The fruits of victory were lost by the Confederate failure to advance. Their victory was rendered almost useless.

By the time they arrived on the hills surrounding Chattanooga, the Federals were prepared for a long defense. By September 23rd the Confederates occupied Lookout Mountain and Missionary Ridge, and a siege of Chattanooga began. James Longstreet, commanding a corps from Lee temporarily detached to help Bragg, wished to attempt a flanking movement, but Bragg refused. He preferred just to wait and starve out Rosecrans, as he had received word that the Yankees only had six days provisions. He extended the Confederate lines to Raccoon Mountain, and placed artillery to cover the roads that ran along the edge of the Tennessee River. Thus blocking the easiest access to the town, he forced the Federals to carry what supplies they could bring across sixty miles of muddy roads.

Rosecrans

When Lincoln got news of Rosecrans's disaster, he decided to reinforce him without delay. Hooker's Corps from Virginia was rushed west by railroad, and Ulysees S. Grant, who had been given command of all the forces from the Allegheny Mountains to the Mississippi, was ordered to march to Chattanooga with 20,000 men. Although when the siege began Bragg had more men, his decision not to assault meant that after a few days Hooker arrived. With these new men the Union garrison outnumbered the Confederate besiegers.

Chattanooga from Lookout Mountain

The Union high command was not impressed with Rosecrans's performance after his defeat at Chickamauga. Charles Dana, assistant secretary of war reported on Rosecrans

I have never seen a public man possessing talent with less administrative power, less clearness and steadiness in difficulty, and greater practical incapacity than General Rosecrans. ... Under the present circumstances I consider this army to be very unsafe in his hands.

Grant eventually decided to replace Rosecrans with George Thomas, the new Federal hero who had held the field at Chickamauga after Rosecrans and most of the army had fled.