| After the Tullahoma Campaign, the Confederate Army of Tennessee had withdrawn to North Georgia. Believing the misinformation that the Confederate Army was retreating in disorder, Union General Rosecrans split his Army of the Cumberland into three corps (under Generals McCook, Crittenden, and Thomas) and had each take widely separate routes to envelope the opposing army. With the arrival of Longstreet's 1st Corps of the Army of Northern Virginia, Bragg's Army of Tennessee was numerically superior to the widely separated Union army and started concentrating near McLemore's Cove in order to corner and defeat each Union Corps in turn. The Confederate plan was to trap the Union army in the valley of McLemore's Cove and cut off the northern escape route to Chattanooga. About this time, Rosecrans recognized the danger to his army and began pulling his forces together. The battle started in earnest on September 19 near Chickamauga Creek. Each army kept feeding units into the battle from the south throughout the day. McCook's Corps was the last of the Union corps to arrive in late afternoon. The fighting in the dense woods went back and forth the first day with heavy fighting all along the line. To the Union forces, the fighting seemed more intense on the Union left (north) in front of Thomas' Corps. Thomas continued to send requests for reinforcement througout the battle. On the morning of the last day (September 20th), there was some confusion about the placement of the Union forces in the thick woods. Thinking there was a gap in the lines, Rosecrans ordered troops north to fill the breach. However, this movement opened a gap in the lines at just the time that Longstreet was attacking with his main force at that same location. Union troops moving north to reinforce Thomas were overwhelmed by the charging Confederates and the retreating front-line troops. Most organized resistance on the Union right (south) broke down as the troops fell back towards Chattanooga. This left only Thomas defending the rear of the Union forces against the entire Confederate Army. The defenders repulsed repeated attacks around their position on Horseshoe Ridge. Their tenacity coupled with timely reinforcement from reserves held off the Confederate attackers until nightfall. During the night, the remainder of the Union army retreated to take up defensive positions in Chattanooga to the north. For his stand, Thomas became known as the "Rock of Chickamauga" and prevented the destruction of the Army of the Cumberland. He would replace Rosecrans as Commander of the Army of the Cumberland in October and hold that position for the remainder of the war. The Illinois regiments which took part in the Battle of Chickamauga are listed below. The links will take you to the regimental pages. | ||
| ARMY OF THE CUMBERLAND | ||