After defeating Braxton Bragg's army at the Battle of Stone's River in January, William Rosecrans made no movement for six months. He wanted to make sure that he was completely prepared before he risked anything. After much urging from President Lincoln, Rosecrans finally launched a campaign against Bragg. He had 65,000 men to the Confederate's 46,000. Instead of trying a direct attack, he would try to destroy Bragg through maneuver.
Bragg had his troops along the Nashville and Chattanooga railroad behind a ridge with only four passes. Rosecrans planed to outflank Bragg. He sent his main column through the east most gap, while at the same time another column would feint in the same direction. He hoped that Bragg would see the smaller column as a feint and look for the attack in the wrong direction. At the same time a detachment of mounted infantry drove deep into Bragg's rear. Rosecrans' plan worked perfectly. By the time Bragg realized that the movements on his right were really not a feint, he was convinced by the raid that he needed to retreat. He fell back all the way to the other side of the Tennessee river. Rosecrans, in what some had called the most brilliant campaign of the war, had driven Bragg from a strong position and out of Middle Tennessee. But the nearly bloodless victory was overshadowed by the capture of Vicksburg and defeat of Lee at Gettysburg, and Bragg's army was still intact, and a battle would still have to be fought.
After this successful campaign, Rosecrans yet again halted. He again refused to move for several weeks to study the terrain and ensure that everything was prepared for another campaign. He would move next on Chattanooga, an important manufacturing and transportation center on the Tennessee-Georgia line.