PRELUDE TO THE EVENT - TULLAHOMA CAMPAIGN - June 23 - July 3, 1863 (Source)
Middle-Tennessee along the Nashville & Chattanooga Railroad. Fearing that large elements of Gen. Braxton Bragg's army would be used to help break the "Seige of Vicksburg" to the southwest, Union officials pressured Maj. Gen. William S. Rosecran to take the offensive against the Confederate army.
For six months following the Battle of Stone's River, Maj. Gen. William S. Rosecrans' Army of the Cumberland regrouped and built up around Murfreesboro, Tennessee. Opposing him, Gen. Braxton Bragg's Army of Tennessee covered the nearby Duck River with a fortified line running left to right, fro the town of Shelbyville to Waltrace on the Nashville & Chattanooga Railroad. Confederate infantry and cavalry under Lt. Gen. Leonidas Polk and Brig. Gen. Nathan B. Forrest held the line's left; infantry and cavalry under Lt. Gen. William J. Hardee and Maj. Gen. Joseph Wheeler took the right. Approaches to the right were covered by infantry and artillery detachments at Liberty, Hoover's, and Bellbuckle gaps. Bragg's headquarters and depots were at Tullahoma, on the railroad 15 miles southeast of Wartrace.
Fearing that large elements of Bragg's command would be used to help break the Seige of Vicksburg to the southwest, Union officials pressured Rosecrans to take the offensive. He yielded, alerting the troops to march on the 24th. He planned a feint against Shelbyville with Maj. Gen. Gordon Granger's corps, while 3 other corps massed against Bragg's right.
Maj. Gen. Alexander M. McCrook's corps, advancing on Wartrace, penetrated Liberty Gap, compelling Confederates to retire on Bellbuckle. Maj. Gen. George H. Thomas' troops thrust toward Manchester, routing Confederates from Hoover's Gap. Maj. Gen. Thomas L. Crittenden's corps, on hte Union left and rear, occupied Bradyville, while Granger's, on the right, felt its wat towards Shelbyville. Union horse soldiers, screening Granger's corps, drove Confederate cavalry from Guy's Gap and into Shelbyville entrenchments.
The rain that had begun on the 24th continued for days, slowing the Union's march. But on the 26th, Thomas' columns pressed ahead and on the 27th, occupied Manchester, flanking Bragg's Shelbyville-Wartrace line. The Confederates pulled back to Tullahoma. While his divisions converged on Manchester, Rosecrans sent a flying column on the 28th, to strike the railroad in Bragg's rear. It arrived too late to destroy the Elk River railroad bridge, but infantry tore up hudreds of yards of track at Decherd.
Satisfied that his position in Middle Tennessee was untenable, Bragg called for a retreat. After the Federals crossed the Elk on July 3rd, the pursuit and the Tullahoma Campaign ended. Bragg's army moved across the Cumberland plateau and took position behind the Tennessee River. Rosecrans called a halt.
During the campaign, Rosecrans' army, at a cost of 560 killed, wounded, and missing, had repeatedly outmanuevered Bragg, compelling him to withdraw 85 miles and evacuate several formidable positions with the loss of 1,634 prisoners, 11 cannon, & large quantities of supplies.