Chickamauga Campaign

The Chickamauga Campaign of the American Civil War was a series of battles fought in northwestern Georgia from August 21 to September 20, 1863, between the Union Army of the Cumberland and Confederate Army of Tennessee. The campaign started successfully for Union commander William S. Rosecrans, with the Union army occupying the vital city of Chattanooga and forcing the Confederates to retreat into northern Georgia. But a Confederate attack at the Battle of Chickamauga forced Rosecrans to retreat back into Chattanooga and allowed the Confederates to lay siege to the Union forces.

In his successful Tullahoma Campaign in the summer of 1863, William S. Rosecrans moved southeast from Murfreesboro, Tennessee, outmaneuvering Braxton Bragg and forcing him to abandon Middle Tennessee and withdraw to the city of Chattanooga, suffering only 569 Union casualties along the way. Union general-in-chief Maj. Gen. Henry W. Halleck and President Abraham Lincoln were insistent that Rosecrans move quickly to take Chattanooga. Seizing the city would open the door for the Union to advance toward Atlanta and the heartland of the South. Chattanooga was a vital rail hub (with lines going north toward Nashville and Knoxville and south toward Atlanta), and an important manufacturing center for the production of iron and coke, located on the navigable Tennessee River. Situated between Lookout Mountain, Missionary Ridge, Raccoon Mountain, and Stringer's Ridge, Chattanooga occupied an important, defensible position.

Although Braxton Bragg's Army of Tennessee contained about 52,000 men at the end of July, the Confederate government merged the Department of East Tennessee, under Maj. Gen. Simon B. Buckner, into Bragg's Department of Tennessee, which added 17,800 men to Bragg's army, but also extended his command responsibilities northward to the Knoxville area. This brought a third subordinate into Bragg's command who had little or no respect for the commanding general. Lt. Gen. Leonidas Polk and Maj. Gen. William J. Hardee had already made their animosity well known. Buckner's attitude was colored by Bragg's unsuccessful invasion of Buckner's native Kentucky in 1862, as well as by the loss of his command through the merger. A positive aspect for Bragg was Hardee's request to be transferred to Mississippi in July, but he was replaced by Lt. Gen. D.H. Hill, a general who did not get along with Robert E. Lee in Virginia. The Confederate War Department asked Bragg in early August if he could assume the offensive against Rosecrans if he were given reinforcements from Mississippi. He demurred, concerned about daunting geographical obstacles and logistical challenges, preferring to wait for Rosecrans to solve those same problems and attack him. He was also concerned about a sizable Union force under Maj. Gen. Ambrose E. Burnside that was threatening Knoxville. Bragg withdrew his forces from advanced positions around Bridgeport, which left Rosecrans free to maneuver on the northern side of the Tennessee River. He concentrated his two infantry corps around Chattanooga and relied upon cavalry to cover his flanks, extending from northern Alabama to near Knoxville.

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