Early on the morning of September_19, 1863 Col. Daniel McCook was ordered to give William S, Rosecrans army a little more protection as it moved north towards Chattanooga, Tennessee by destroying Reed's Bridge over Chickamauga Creek. As McCook advanced he brushed up against the extreme rear of Confederate General Bushrod Johnson's division.
Shortly after midnight McCook set the bridge on fire and reported a brigade of Rebels in the area to George Henry Thomas. What McCook thought was a brigade of Rebels was actually the extreme rear of Longstreet's Corps. General John Croxton was sent forward to flush out McCook's "Rebel brigade" and at 9:00am wired Thomas from Jay's Mill, "Which of the 4 or 5 Rebel brigades do you want me to flush out?" The battle of Chickamauga had begun.
Senior Union officers thought that the Confederates were still east of Chickamauga Creek and were shocked when they finally realized the majority of the Confederates under Braxton Bragg were already across the creek.
Neither Bragg nor Rosecrans wanted to fight in the heavy underbush south of Chattanooga. Visibility was limited to 150 feet, less than the range of a rifle. Cannon were useless, except in the occasional field that broke the heavy forest. Battle lines were broken by physical obstacles and enlisted men made tactical decisions. Often the fighting was hand-to-hand. Both generals realized that neither would come out a clear winner under these conditions. Yet, just as at Gettysburg, the field on which the men fought was not the choice of generals but the choice of fate.
While John Bell Hood struggled to keep James Longstreet's Corps moving south and west towards Lee and Gordon's Mill, Bragg's men were moving due west toward the road between Chattanooga and Lafayette, Georgia. All day Thomas's Army of the Cumberland slowed the Rebel movement toward Lafayette Road while the main body of his army built a strong position just west of the road to Chattanooga.
The brunt of the initial conflict was borne by Union General George Thomas and Confederate General Leonidas Polk, but the first Confederates to be heavily engaged was Liddell's Division (under W. H. T Walker) who struck Absolam Baird's First Division, XIV Corps, Army of the Cumberland. George Thomas moved Baird forward to support the smaller engagement near Reed's Bridge. Before Baird got past the Winfrey House, Liddell's men exploded on the Union right, disorganizing Baird's men and driving them back.
When Confederate Frank Cheatham moved to support Liddell he ran into John Palmer's Second Division at Brock Field. Technically part of Thomas Crittenden's command, Palmer was moving to support Baird under George Thomas. Beginning at 1:00 pm for about two hours Cheatham and Palmer engaged in what author Steven Woodworth described as a "slugfest."
The rest of Crittenden's force, which included elements of Alexander McCook's Corps because of the complex movements that Rosecrans ordered, was marching north on LaFayette Road between Viniard House and Brotherton Cabin when Hood arrived east of the road before 2:00pm. Quickly regrouping Hood's Confederates continued their westward movement towards the LaFayette Road. Crittenden's men, aware of the Rebel presence, created a bulge in the Union line by pushing their line east and building some quick breastworks to give the Yankees more room.
Longstreet's Corps (under Hood) had been moving all day and had little if any rations or water. Still, his men advanced as ordered. After repeated charges and counter-charges the Confederates captured Viniard Farm and controlled Layfayette Road. As the Confederate's approached Widow Glenn's house, John Wilder's Lightning Brigade struck four times with their breach-loading Spencer Rifles to prevent Hood from consolidating his gains.
Earlier in the afternoon, Confederate General A. P. Stewart began a series of attacks in the area of Brotherton Cabin. With the disruption caused by Hood near Viniard's, when Stewart sent in his reserve (under William Bate) at about 3:30pm they breached the Union line.
Union General Phil Sheridan was moving north west of Lafayette Road when Rosecrans sent Sheridan orders to attack. The aggressive Sheridan did not need more than that to advance on Hood's exhausted troops. As they withdrew Union resistance near Brotherton Cabin strengthened, driving A. P. Stewart's men back as well. By sunset Rosecrans held all of LaFayette Road, although Thomas had to withdraw to a high point near Kelly's farm. During the evening of the 19th Rebels could hear the Federals cutting trees and building breastworks.
As part of a larger plan, Bragg ordered Daniel Harvey Hill's Corps to attack the Union line at dawn on September 20. Hill, who missed the meeting, did not receive the orders until that morning when a furious Bragg delivered them in person. Ordered to begin the attack immediately, Hill delayed until 9:00am. As the attack began, Hill's men pierced the Union line, moving on Thomas' flank. The men had driven into the rear before being repulsed by reinforcements.
Overnight, Bragg organized his men into two wings, the Left Wing (southern) under Longstreet and the Right Wing (northern) under Polk. Longstreet would command Simon Bolivar Buckner Corps and Hindman's Division from Polk's Corps while Polk would command Daniel Harvey Hill's Corps and W. H. T. Walker's Corps and division commander Frank Cheatham from his own Corps.
Site of Widow Glenn's House(Rosecrans' Headquarters). Col. Wilder's Lightning Brigade attacked Longstreet's advancing Rebels.
Communications hampered the morning attack at the north end of the Union line to be initiated by Daniel Harvey Hill at 5:00am. When Polk finally got a message to Hill at 5:30am Hill appealed directly to Bragg to delay the attack. Bragg agreed and delayed the initial movement to P:00am. When Hill finally ordered his men to attack at 9:30, the Confederates advanced on strong Union defenses.
George Thomas began to look for support from nearby commanders to repel the Confederate attack. Thomas Wood, commander of a Union division near Brotherton Cabin withdrew to support Thomas. Normally, as this occurred the two sides would move closer or other men would move in. When Wood completed his withdrawal from the line at just before 11:00 am, neither happened correctly. A much smaller group did move in and some men did try to close up the line, but a hole still existed.
Unaware of the federal blunder Longstreet ordered Hood to advance just after 11:00am. Tennessee lawyer John S. Fulton led his brigade in the attack on Union lines, only to find the hole left by Tom Woods' departure. Fulton found the hole and worked to keep most of his men moving ahead. With Evander McNair on his right and John Gregg behind him, Fulton took the initiative simply because he had the support he needed to advance behind enemy lines. Neither Bushrod Johnson (division commander) or John Bell Hood (Corps commander) were involved in the actual breakthrough.
In all, 8 Confederate brigades, including all three of those under Bushrod Johnson, pushed through the gap that expanded to 0.5 miles north from the south side of Brotherton Cabin. Hood did move forward and wheel his troops to the north, hoping to rout the remaining Union line. Union Generals Horatio P. Van Cleve and Charles G. Harker (a brigade commander under Tom Woods) were trying to slow down the Confederate advance.
While trying to rally his old Texas Brigade, which had become disorganized as it advanced on Van Cleve, Hood was shot in the leg. It is frequently stated that this loss slowed the Confederate advance, but by this time the advance had already lost a good deal of momentum.
General George Thomas, on Snodgrass Hill, was the only Union force remaining on the battlefield north of the Confederate breakout. To protect Union soldiers fleeing the Rebels, Col. John Wilder ordered his Lightning Brigade to attack. The mounted infantry, armed with Spencer repeating rifles struck Arthur M. Manigault's brigade, slowing Longstreet's advance long enough for Thomas to reform his line and to allow Rosecrans to escape. Wilder was ready to take on the rest of the Confederate Army, but Assistant Secretary of War Charles Dana stopped him.
Rosecrans, commander of the Army of the Cumberland, decided to try to reach Thomas's position north of the Confederate breakthrough on Dry Valley Road. Alexander McCook joined him, just as Tom Crittenden did later, but future President James Garfield convinced them that rejoining Thomas was futile. Instead, Garfield escorted them to McFarland Gap and returned from the gap to Thomas at Snodgrass Hill after seeing the generals off on their return to Chattanooga.
As Union soldiers approached the Horseshoe Ridge today known as Snodgrass Hill, Thomas and other officers issued orders from horseback directly to retreating soldiers. Repeated Rebel assaults could not break the thin blue line Thomas constructed. Listening to the battle from Rossville, General Gordon Granger advanced his Reserve Corps without orders, resupplying Thomas and protecting his flank. For more, see Granger saves the Federal Right
For his bravery, Thomas became known as "The Rock of Chickamauga."
His Civil War career over, Old Rosy issued a telegram from Chattanooga to his superiors in Washington saying, "We have met with a serious disaster...we have no certainly of holding our position here." A second wire to the beleaguered Thomas instructed him to withdraw to Chattanooga.