After the Battle of Chickamauga, the victorious Army of Tennessee, with General Braxton Bragg in command, marched north forcing the Army of Cumberland to retreat. While retreating, the Army of Cumberland found themselves a few days ahead of the Confederates. Having a day or two, Major General George H. Thomas, in command of the Army of Tennessee, decided setup a defense line in the city of Chattanooga. At the time, the city of Chattanooga consisted of 2,545 people and was considered a citadel for whoever was in control of the city. Geographically, Chattanooga is located in a valley in southeast Tennessee, by the Rossville Gap.

Upon arrival, Major General Thomas transformed the town. In the center of the town, there is the Crutchfield's Hotel, which once had the Stars Bars, now was dominated with the Union Flag. Since the lack of trees in the valley, smaller estates were tore down for their wood and were used for military proposes. Within two weeks, beautiful houses were transfigured into hideous military fortresses. Soon, rifle pits were run through the local graveyard and massive water lines were built from the river to the city. Inside the citadel, the Union Army tore down fences, houses, barns and sheds. Chattanooga had literally become a walled city.

Once General Bragg and his troops arrived at Chattanooga, they partially encircled the Chattanooga valley suffocating the Union troops. Thomas' troops, already short of food were immediately on short rations. The only incoming source of food for the troops was supplied by a 60-mile wagon route, across Walden's Ridge. Famine became a more pressing enemy then Bragg's Army. By the third week on short rations, Union troops were placed on quarter rations.

With things already bad for Major General Thomas, they got worse. Thomas was replaced by General Ulysses S. Grant. The Union sent Grant in this only to try and have troops evacuated with minimally casualties. Before Grant arrived, Thomas promised that he would hold his troops in Chattanooga until they starve.