Union Major General William S. Rosecrans was the first commander of the Army of the Cumberland when it was formed on October 24, 1862. The army defeated a Confederate army under Braxton Bragg at the Battle of Stones River (December 31, 1862-January 2, 1863). The army remained static, camped at Murfreesboro Tennessee for six months. In June 1863 Rosecrans began a campaign of manoeuver to drive Bragg from Tennessee which culminated in the Battle of Chickamauga on September 18-20, 1863. A fatal misstep by Rosecrans allowed Confederates under James Longstreet to route a third of the Army of the Cumberland, total defeat only being staved off by a desperate defense by George Thomas, “the Rock of Chickamauga”. The army retreated to Chattanooga where it was besieged by Confederates under Braxton Bragg. Rosecrans was relieved and replaced by Thomas. A relief force was sent to Chattanooga and lifted the siege, with the Army of the Cumberland redeeming itself by a spectacular attack on Confederate positions in the Battle of Missionary Ridge on November 25, 1863. Rebuilding in the spring of 1864 the Army of the Cumberland participated in Sherman’s Atlanta Campaign. At the end of the Atlanta Campaign the Army of the Cumberland ceased to exist as a separate organization and its units became part of Sherman’s army in the March to the Sea.
The Army of the Cumberland was born on October 24 1862, when Union Major General William Starke Rosecrans was assigned command of the newly created Department of the same name. Rosecrans replaced Major General Don Carlos Buell at the helm of the Army of the Ohio, after Buell's force curtailed a Confederate invasion of Kentucky, but failed to destroy the invading enemy army under General Braxton Bragg.
Initially, the troops in Rosecrans's new department were simply called the XIV Corps, further subdivided into three wings: Center, led by Major General George Henry Thomas, Left, headed up by Major General Thomas Leonidas Crittenden, and Right, commanded by Major General Alexander McDowell McCook. Thomas and McCook were West Pointers. Crittenden was a political appointee from a highly influential Kentucky family. Rosecrans also brought Major General David Sloane Stanley, another academy man, to take charge of his cavalry.
With a new headquarters in Nashville. Rosecrans was charged with restoring Middle and East Tennessee to Union control. Braxton Bragg’s Rebel army, newly rechristened as The Army of Tennessee, took up station at Murfreesboro. Thus began one of the great adversarial relationships of the war, second only to that between the Union Army of the Potomac and Robert E. Lee's Army of Northern Virginia.
Rosecrans inherited an army numbering approximately 67,000 men, but of those, only 40,000 effectives were ready to take the field. He also inherited a precarious supply situation. Confederate cavalry raids severely damaged the Louisville & Nashville Railroad, which would not be restored until November; and the Cumberland River was so low that most vessels could not navigate it as far as Nashville. As a result, many Federals were tied up as garrisons, and any advance would have to wait until sufficient supplies were on hand.
The men in the ranks welcomed the change in leadership. They never warmed up to Buell. Buell built the army, bringing order out of the chaos that was the rush to war in 1861, but he lacked the charismatic touch that so inspired volunteers. Buell was an old army man, with old army ways. When Rosecrans arrived, one newspaperman noted that "the army threw up its hat in delight." Colonel Benjamin Franklin Scribner thought Rosecrans impressed the troops "by his open and genial manner, contrasting agreeably with the taciturn exclusiveness of ...Buell."
Two months after assuming command, with the army ready for field service once again, Rosecrans launched the Army of the Cumberland's first offensive, a multi-pronged advance against Bragg at Murfreesboro. The effort resulted in the bloody Battle of Stones River, fought from December 31, 1862, and January 2, 1863.
Both Bragg and Rosecrans conceived of the same battle plan. Each intended to attack the other's right flank. Stones River bisected the battlefield, and bisected each army’s front. Rosecrans planned to send Crittenden’s Wing across to the east bank of that stream to capture the town of Murfreesboro. Bragg had massed most of his army on the west bank and aimed to strike Rosecrans’s Right, under McCook. At dawn on New Year’s Eve, Bragg struck first.
In the first day’s fight the Rebels achieved a tactical success, all but routing McCook’s command, but failed to completely drive the Federals from the field. New Year’s Day was quiet; both armies were exhausted. A final Confederate blow on January 2 failed to produce any important results. Overall losses were about equal; roughly a quarter of each army. However, Bragg opted to retreat, leaving the field— and a victory —to Rosecrans. Coming on the heels of disaster in Virginia, Bragg's withdrawal converted a tactical stalemate into a badly needed Union victory. On December 13 the Federals had suffered a disaster at Fredericksburg Virginia, losing 13,000 men in fruitless attacks, which plunged the North into despair. Rosecrans's success was met with jubilation, a sign that the war was not such a failure after all.
For the next six months, the Army of the Cumberland remained static, with the main body camped in and around Murfreesboro. For his part, Bragg defended a series of gaps in the Highland Rim, the high ground that ringed the Nashville basin, and established a new base at Tullahoma. Though the two armies fought no major battles during this period, the spring and summer of 1863 were marked by a series of small engagements between elements of each command.
That spring, Rosecrans’s focus was on re-organization. The unwieldy wing structure was scrapped. Thomas retained command of the XIV Corps, now including four divisions. McCook’s Right Wing became the XX Corps, while Crittenden’s wing was renamed the XXI Corps; each man leading three divisions. The army’s large numbers of garrison troops were integrated into the newly formed Reserve Corps, led by Major General Gordon Granger. Rosecrans also greatly augmented his cavalry, expanding it into a 10,000 man corps of two divisions, still headed up by Stanley. In pursuit of this goal, Rosecrans bombarded the War Department with ceaseless requests for horses, men, and the most modern arms— breech-loading or repeating carbines and rifles— all of which exasperated President Lincoln, Secretary of War Edwin McMasters Stanton, and General-in-Chief Henry Wager Halleck. Rosecrans’s incessant demands, all delivered in a hectoring tone, eroded the good will earned at Stones River, souring relations between himself and Washington. Finally, always mindful of the precarious nature of his supply lines, Rosecrans accumulated months’ worth of surplus rations in forward depots in order to make sure he wouldn’t be caught short if the Rebels again disrupted rail traffic in his rear.
Washington wanted action, not delays, for things were stirring elsewhere. In Virginia, the Army of the Potomac suffered another crushing defeat in early May, at Chancellorsville. In Mississippi, Major General Ulysses S. Grant opened latest effort aimed at capturing Vicksburg, the Confederate bastion on the Mississippi River. Lincoln worried that without similar action from Rosecrans, the Rebels could send troops from Bragg’s army in Tennessee to help other theaters. Rosecrans insisted that this was not the case, but in fact by early June, Bragg had indeed been ordered to send sizeable reinforcements to Vicksburg. Nor were affairs in the east quiet after Chancellorsville: in mid-June, Robert E. Lee’s Army of Northern Virginia began heading north in what would turn out to be the invasion of Pennsylvania, culminating in the battle of Gettysburg.
On June 24 the Army of the Cumberland commenced their own campaign against Bragg's forces. The Federals numbered 60,000 troops. Bragg had less than 40,000 men, but had the advantage of favorable terrain. Rosecrans again resorted to a turning movement, feinting at Bragg's front with Stanley's Cavalry and McCook's XX Corps while the XIV and XXI Corps attempted to slip around Bragg's eastern flank to seize the Confederate supply depot at Tullahoma. Initially the Federals met success, winning small but important fights at Hoover's and Liberty Gaps. Hoover's Gap was especially notable, for it highlighted the tactical success of Rosecrans's mounted infantry concept. Indiana Colonel John Thomas Wilder led his mixed Illinois and Indiana brigade rapidly through the gap to seize the southern end, and then held it against Confederate counterattacks until reinforcements could arrive. This action earned Thomas's praise and Wilder's men a new sobriquet: going forward they were known as the "Lightning Brigade."
Despite this good beginning, heavy rain hampered the campaign, and Bragg escaped to Chattanooga. Though the Army of Tennessee escaped to fight another day, their rapid abandonment of Middle Tennessee was a hugely demoralizing blow to the Rebels in the ranks. Union losses were minimal, with less than 500 casualties.
Rosecrans's success was greatly overshadowed by victories elsewhere. On July 4, the same day that Bragg arrived in Chattanooga, Lee retreated from Gettysburg and Grant accepted the surrender of Vicksburg. Rosecrans, bitter at what he felt was a snub from Stanton, begged the War Department not to overlook what his army had achieved simply because "it was not written in letters of blood." 
Rosecrans's next objective was Chattanooga. The city was a transportation hub, controlling the South's only direct rail connection between Virginia and the Confederacy's western theater. It was also the gateway to the Deep South, offering access through the southern end of the Appalachian Mountain chain into Georgia and the Carolinas. Leveraging Bragg out of the place would be challenging.
Again, Rosecrans opted for a turning movement. His operation would commence simultaneously with a move against Knoxville by Union Major General Ambrose Burnside, from Kentucky; while Burnside threatened Chattanooga from the northeast Rosecrans's army crossed the Tennessee River below the city. From there, Rosecrans could either strike directly at Chattanooga or better still, move against Bragg's own lifeline, the railroad running south to Atlanta, without which Bragg's army would starve.
Rosecrans began crossing the Tennessee River at the end of August, 1863. Bragg responded by retreating again, allowing Union troops to occupy Chattanooga without a fight on September 9. This time, however, Bragg was not running away. Heavily reinforced from Mississippi and Virginia, the Confederates tried to lure Rosecrans into a trap and destroy his army one corps at a time. For a week, both armies tried to out-maneuver each other in North Georgia. These operations culminated in the bloody Battle of Chickamauga, fought on September 18-20, 1863.
Chickamauga was the second bloodiest battle of the war, producing nearly 35,000 losses out of a combined total of 120,000 engaged. On September 18 the Union mounted forces again played a critical role, delaying Bragg's planned attack by a whole day. The next day was marked by confused, back-and-forth fighting in the woods, with neither side gaining any particular advantage. September 20, however, saw Rosecrans make a fatal misstep. A misinterpreted order led him to open a gap in his defensive lines just as a powerful Confederate offensive column stepped off. This Rebel force, commanded by the newly-arrived Lieutenant General James Longstreet from Lee's army in Virginia, shattered Rosecrans's right, routing the Union XX Corps and driving one third of the Federals from the field. Only a desperate defense by George Thomas saved the day. The battered Federal army retreated as far as Rossville on September 21, and retreated again the next day, this time into the defenses of Chattanooga itself. Bragg eschewed the idea of a direct assault, opting instead for a siege.
Though the Confederates were unable to completely seal off the city, the last supply path open to the Federals was a torturous sixty mile wagon route across the forbidding heights of Walden’s Ridge, a road that would have been inadequate in the best weather, and, with the coming of heavy October rains and the promise of winter looming, reduced the Army of the Cumberland to starvation rations. With surrender or retreat seemingly likely, the Federal government responded by sending massive reinforcements and a new overall commander, Ulysses S. Grant, now given overall direction for the Union war effort in the West.
Chickamauga wrought great changes to the Army of the Cumberland. Within a month, Rosecrans was relieved of command, replaced by Thomas. Thomas Crittenden and Alexander McCook were also sent packing; they had also been swept off the field by the tide of battle and ridden all the way back to Chattanooga instead of trying to rejoin Thomas on the field. The Union XX and XXI Corps were broken up and merged into the XIV Corps and Granger’s Reserve Corps, the latter now renamed as IV Corps. Reinforcements from the XI and XII Corps, Army of the Potomac, were shipped west under command of Major General Joseph Hooker to join Thomas. Additionally, Grant directed four divisions from his own Army of the Tennessee—now commanded by Major General William Tecumseh Sherman since Grant’s elevation— to rush to Georgia from Mississippi.
These powerful forces all combined to turn to the tables on Braxton Bragg. His victorious Confederate Army of Tennessee was almost as wracked by dissension as Rosecrans’s force was by defeat, and through the months of October and November the Rebels re-shuffled corps commanders and bled troops away to other theaters. At the end of October the Federals re-opened a sustainable supply line into Chattanooga, and by the end of November, launched a series of attacks that ultimately lifted the siege and all but routed Bragg’s men. Key among these attacks was a daring—and unauthorized— attack by the Army of the Cumberland against Bragg’s main position on Missionary Ridge, a spectacular charge that did much to restore the Cumberlander’s spirit and sense of pride. The battered Rebels retreated to Dalton Georgia, where it was Bragg’s turn to be replaced, by General Joseph Eggleston Johnston.
The spring of 1864 was another time of rebuilding for the Army of the Cumberland. Thousands of men re-enlisted, gaining the title of veterans and the chance to go home on furlough. Ranks were filled up with new recruits and drafted men. By that April, the Army of the Cumberland numbered 65,000 men in three infantry and a cavalry corps: The IV Corps, led by Major General Oliver Otis Howard; Thomas’s old XIV Corps, now led by Major General John McAuley Palmer, and the newly reconstituted XX Corps— comprised of those XI and XII Corps men from the Army of the Potomac —commanded by Hooker. The Cavalry also had a new man, Brigadier General Washington Lafayette Elliott, for David Stanley was assigned an infantry division under Howard.
Thomas’s army, though by far the largest single component of the grand force Sherman assembled for his advance towards Atlanta, was just one of three field armies Sherman captained. The Army of the Tennessee under Major General James Birdseye McPherson and the Army of the Ohio under Major General John McAllister Schofield added another 40,000 troops to Sherman’s grand column. Facing them, Johnston’s Rebels numbered 60,000 troops, a force that would rise to 75,000 men once Johnston was reinforced from Mississippi.
The Atlanta Campaign represented a change in the nature of war for the Cumberlanders. Instead of long periods of rest interspersed with active operations which culminated in large, climactic battles; the months between May and September, 1864, represented one continuous grind of marching and fighting of nearly daily skirmishes and episodic larger engagements. None of these were individually decisive, but together they resulted in the capture of Atlanta in early September, a notable achievement.
In early May the Army of the Cumberland was involved in attacks against Rocky Face Ridge, outside of Dalton Georgia, designed to occupy Rebel attention while McPherson’s army slipped around the Confederates’ flank via Snake Creek Gap to strike at the railroad running through Resaca. When McPherson was checked, Sherman ordered his whole force to follow. The Battle of Resaca, on May 14 and 15, involved the Army of the Cumberland in the first heavy fighting of the new campaign. Johnston retreated, and Sherman followed. Another major Union flanking attempt produced fighting at New Hope Church, Pickett’s Mill, and Dallas between May 25 and 28. The hardest of these actions was Pickett’s Mill, where Howard’s IV Corps suffered heavily; so much so that Cumberlanders thereafter referred to it as “the Hell Hole.”
In June, Sherman maneuvered against the Lost Mountain and Kennesaw lines. Major fighting occurred on June 22, when Lieutenant General John Bell Hood’s Confederate Corps attacked the Union XX Corps; and again on June 27, when Palmer’s XIV Corps led an effort to smash the Rebel center at Cheatham Hill. The June 27 assault, in particular, was a bloody failure; Sherman would not try such a frontal attack again.
More Union maneuvering forced Joseph Johnston’s Army of Tennessee back across the Chattahoochee River in early July, removing the last water barrier between Sherman and Atlanta; it also caused Confederate President Jefferson Davis to replace Johnston with Hood on July 17, 1864. Hood promised not to abandon Atlanta without a fight. And fight he did. On July 20, he attacked Thomas’s Army of the Cumberland along Peachtree Creek, and was repulsed with heavy loss.
So far during the campaign, the majority of the heavy action had fallen on the Army of the Cumberland. That changed on July 22, when Hood turned eastward to strike at McPherson’s Army of the Tennessee, in what came to be called The Battle of Atlanta proper. Again Hood’s assaults were rebuffed. Hood’s next attack, at Ezra Church on July 28, again fell on the Army of the Tennessee, now commanded by Howard in the wake of McPherson’s death on the 20. The final battle of the campaign came a month later, on August 31 and September 1, in the two day Battle of Jonesboro, southwest of Atlanta. The brunt of the first day’s action fell again on the Army of the Tennessee. On September 1, however, the XIV Corps’ final attack broke the Confederate lines. This defeat left Hood no choice but to abandon Atlanta for good. The next day, the Union XX Corps, now commanded by Major General Henry Warner Slocum, marched into the city.
The end of the Atlanta campaign also all but finished the Army of the Cumberland as a separate organization. The XIV and XX Corps accompanied Sherman on the March to the Sea, now styled the Army of Georgia. George Thomas resumed departmental command at Nashville. When Hood invaded Tennessee in November, 1864, in a last desperate gamble to divert Sherman and redress southern defeats, Thomas cobbled together various forces, including the IV Corps, Schofield’s Army of the Ohio, and parts of the Army of Tennessee to oppose him, but most of the Army of the Cumberland’s best fighters were far away with Sherman. The army forged into such true steel by the past two years of war in Kentucky, Tennessee and Georgia was no more.
Daniel, Larry. Days of Glory: The Army of the Cumberland, 1861-1865. Baton Rouge: Louisiana State University Press, 2006.
Cozzens, Peter. No Better Place to Die. Champaign: University of Illinois Press, 1990.
———. This Terrible Sound. Champaign: University of Illinois Press, 1992.
———. The Shipwreck of their Hopes. Champaign: University of Illinois Press, 1994.
Fitch, John. Annals of the Army of the Cumberland. New York: Lippincott, 1864.
Powell, David A. The Chickamauga Campaign, vol. 1. A Mad Irregular Battle. El Dorado Hills, CA: Savas Beatie, 2014.
———. The Chickamauga Campaign, vol. 2. Glory or the Grave. El Dorado Hills, CA: Savas Beatie, 2015.
Van Horne, Thomas B. History of the Army of the Cumberland, Cincinnati: Robert Clark, 1875.
No organizations listed.
Near the end of the Civil War, veterans of the Army of the Cumberland commissioned the artist William D. T. Travis to memorialize the career of General William Starke Rosecrans and his campaigns in Kentucky and Tennessee. The panorama was shown from 1865 to 1871. Today it is too fragile for display. The Smithsonian has created a video showing the panorama and recreating how it would have been presented using the original narration.
Major General George H. Thomas and The Army of the Cumberland is a website devoted to exploring the history of the army and the personalities that served in its ranks.
Chickamauga-Chattanooga National Military Park
The National Park Service operates the Chickamauga-Chattanooga National Military Park. The Chickamauga Battlefield Visitor Center is open daily from 8:30 a.m. to 5:00 p.m. and the Lookout Mountain Battlefield Visitor Center is open daily from 9:00 a.m. to 5:00 p.m. Both Visitor Centers are closed on Christmas Day and New Year’s Day. The park is located at 3370 LaFayette Road, Fort Oglethorpe, GA 30742.
Stones River National Battlefield Park
The National Park Service operates the Stones River National Battlefield Park. The Visitor Center is open daily from 8:00 a.m. to 5:00 p.m. and is closed for Thanksgiving and Christmas. The park is located at 3501 Old Nashville Highway, Murfreesboro, TN 37129.