After the regrouping of the Federals by Rosecrans, and the movement of Bragg from Chattanooga towards Lafayette, the scene was ready for Battle to open, and the first moves would come on the 18th September.

The map above shows the main crossings of Chickamauga Creek, the main roads that would be used, as well as some of the main farms.

The Federals were on the west of the Chickamauga Creek, with the Confederates on the east side. Bragg would need to move his forces to the west side, and he hoped that by crossing at Reed’s Bridge and Alexander’s Bridge that he would be able to position himself between Rosecrans and Chattanooga, and fold up the Federals from the north.

Rosecrans needed to respond to Bragg’s encircling maneuvre in the north by himself moving some of his units north of Lee & Gordon’s Mill, and while Crittenden’s force was the most northerly he elected to use Thomas. This meant Thomas’ corps spending the night of the 18th marching north on the road through Crawfish Springs, across the rear of Crottenden’s force to take up their new positions on Rosecrans’ left wing. With Baird’s division leading, followed by Brannan and Reynolds, the head of the march passed through Crawfish Springs at 2a.m. on the 19th. At sun-up on that Saturday Thomas, with Baird’s division, reached the Kelly House, and at 8a.m. Brannan crossed Baird’s rear to take up position as the left most division of Rosecrans’ army. Rosecrans moved his HQ north from Crawfish Springs to the Widow Glenn House.

With Polk still facing Crittenden at Lee & Gordon’s Mill, Bragg was unaware of Thomas’ move and how far north Rosecrans’ left wing was now positioned.  Because of this leftward move by Thomas, Bragg’s move over the Chickamauga Creek would not put him between Rosecrans and Chattanooga, so allowing him to fight the Federals facing south. He would have to fight facing west with the Chickamauga Creek at his back.

Lee & Gordon’s Mill