Chattanooga- Second Battle

As part of the Chickamauga Campaign, Maj. Gen. William Rosecrans (Army of the Cumberland) ordered a brigade to shell Chattanooga from the western side of the Tennessee River and skirmish with the main Confederate force in the city to divert attention away from the flanking column sent southwest of the city. Other Union units were deployed along the river to the east. The diversion was successful, with Gen. Braxton Bragg (Army of Tennessee) concentrating his army east of Chattanooga. After concluding that his position was untenable, Bragg abandoned the city on September 6 and retreated into northern Georgia.  (Cozzens, Peter. This Terrible Sound: The Battle of Chickamauga. Urbanna, Illinois: University of Illinois Press, 1992)