Disunion follows the Civil War as it unfolded.  The Battle of Chickamauga, which took place in northwest Georgia on Sept. 19 and 20, 1863, was one of the bloodiest battles of the war, and a near disaster for the Union. Indeed, what might have been a game-changing defeat for the North was averted largely thanks to the battlefield leadership of a single man, Gen. George Thomas. While the Union ultimately fled the field, Thomas’s stalwart stand against an overwhelming Confederate assault saved thousands of men, who were then able to regroup and continue the Union push into Georgia.  Thomas was born in 1816 and raised in Southampton County, Va. His family was part of the planter class and not especially wealthy when Thomas was born. But over time it grew in affluence to be among the wealthiest in the county: by 1829 the Thomas family held 685 acres and 24 slaves. Certainly one of the defining moments of Thomas’s young life was his survival of the 1831 Nat Turner rebellion, when Thomas, his mother and several of his siblings narrowly evaded a mob of rebelling slaves.  Thomas arrived at West Point in the summer of 1836. For roommates, he was paired with Stewart Van Vliet and William Tecumseh Sherman, both future fellow generals, and the three became close friends. Life at the academy was hard, as cadets faced an endless parade of drills and inspections, spartan quarters ill-suited for winter and bland food and constant hunger. Alcohol and tobacco were banned, and students were restricted from even innocuous activities like playing chess. Thomas was reserved to the point of stoicism. His seriousness, combined with his slightly older age and his height, led some his classmates to nickname him Old Tom and even General Washington. He was an excellent student, rising each year, and he graduated 12th of 40, earning an artillery commission. Students not commissioned as engineers could be expected to be shipped west to the frontier or south. Thomas was sent to Florida.  When Thomas arrived in December 1840, the United States was still embroiled in the Seminole Wars. Nearly 1,500 troops died during this second iteration of the Seminole Wars, but only 328 in battle, the rest from the scores of tropical diseases including dysentery and malaria. Because of his competence, Thomas was initially excluded from patrols and was placed in charge over most administrative duties to ensure adequate supplies and food. Thomas wrote that he was “very much pleased” by the work, but over time grew dissatisfied with the harsh, boring existence. But his time in Florida taught him the pivotal importance of supply lines.  In June 1845 Thomas’s unit was sent to Texas, where it joined up with Gen. Zachary Taylor’s forces in anticipation for war with Mexico. Moving south in March 1846, Thomas saw action at Fort Brown, Palo Alto and harsh fighting in Monterrey. Thomas was part of the force attacked by Santa Anna at the Battle of Buena Vista. Eventually the Americans prevailed, and for his bravery Thomas earned his third brevet promotion in seven years, becoming a captain by the end of 1847 – a movement the historian Francis McKinney notes “marked Thomas as one of the outstanding junior officers in the army.”  Thomas’s time in Mexico had been valuable in learning the importance of drills to prepare men and instill discipline under fire, the crucial importance of supply and logistics, and how to engage an enemy on his own terrain and on the defensive. At Buena Vista he had had to fight defensively and react flexibly to emerging circumstances as opposed to following the precepts of a textbook. As the historian Freeman Cleaves argued, his experiences in Mexico “contributed to Thomas’s innate sense of caution” and solidified his desire “insisting on establishing fixed bases of supplies … before advancing very far into enemy country.” In time this approach would sometimes unfairly hinder Thomas in the eyes of his peers as a great defensive general, but one who was slow to move beyond set supplies, whereas Grant and Sherman would often leave their bases and live off the land.  During this time, advancement was almost impossible as the military downsized and many officers left for the private sector, including Grant and Sherman. That Thomas remained in the Army, enduring brutal, unglamorous assignments, is telling of his dedication to the nation and his job. At Bragg’s recommendation, Thomas was hired as an instructor at West Point in 1851, where he taught J.E.B. Stuart, Fitzhugh Lee, Philip Sheridan and Bell Hood, whom he would face off with at the Battle of Nashville.  In 1854 Thomas was shipped west to head Fort Yuma, and then to the newly formed Second Cavalry in Texas. There he joined an astonishing group of talent including Albert Sidney Johnston, Robert E. Lee, William Hardee, Earl Van Dorn, Edmund Kirby Smith and George Stoneman, a group that, as one author has noted, “supplied more officers to high command than any unit in military history.”  From his diverse log of assignments, Thomas held two critical markers of experience. First, he had now gained time in all three branches: infantry in Florida, artillery in Mexico and cavalry in Texas. Second, in protecting the movements of Native Americans, his exposure to the persecution and direct violence they faced from settlers, combined with his time in Yuma and Fort Lauderdale, demonstrated to him the complexity of race relations, something that likely also expanded to his own friendly upbringing with many slaves.  These latter experiences are critical in assessing Thomas’s decision to remain in the Union Army in 1861, rather than join the Confederacy like many of his Southern peers. Thomas’s decision was not well received by his fellow Southerners. Stuart called him a “traitor” and wished to see him hanged. Members of his own family were incensed, particularly his sister, who remained on the family plantation and wrote that Thomas “had been false to his state, his family, and to his friends” and effectively disowned him.  Once the war began, Thomas was sent west to Kentucky as a brigadier general and was placed in charge of Camp Dick Robinson, tasked with training 6,000 raw recruits. But when Lincoln ordered an invasion of Union-friendly Eastern Tennessee, Washington placed another general in charge of the troops Thomas had trained, the first of many slights Thomas would endure during the war.  Undeterred, Thomas acquitted himself well during the first years of the war. He met and defeated a Confederate invasion force at Mill Springs in Kentucky, an impressive, albeit minor, victory (of only around 4,000 men on each side). He then joined with Gen. Don Carlos Buell in Nashville and moved south, arriving at Shiloh the day after the battle. While the North defeated Southern forces, Grant was criticized for being unprepared and Gen. Henry Halleck assigned Thomas four of Grant’s divisions, placing him at some odds with Grant, which would ill-serve him later.  After Halleck’s overly cautious monthlong slog to Corinth, Thomas was reunited with Buell in a two-month trek back to Tennessee. The slow pace infuriated Washington, with many leaders demanding Buell’s ouster and replacement by Thomas. Thomas’s rebuffed calls against Buell, showing a pattern of loyalty to superiors and a hated for political interference that was commendable, but, along with his Southern heritage, would deny him posts of independent command in the future. When Buell was finally relieved after his unspirited attack at Perryville in October, Thomas was passed over and the command went to Gen. William Rosecrans, who’d graduated from West Point two years after Thomas and held less seniority.  Union forces fought Braxton Bragg to a stalemate at Stones River on New Year’s 1863, with Thomas’s leadership critical. Rosecrans pushed Bragg back to Chattanooga relatively bloodlessly in late June, and took the city when the Confederates left in September. After moving into Chattanooga, Rosecrans finally wanted to go after Bragg’s forces, but Thomas correctly saw that the army could be threatened by over-aggression and urged caution. He was rebuffed by Rosecrans, who moved men into the area around Chickamauga Creek on Sept. 17.  Bragg’s force was reinforced by James Longstreet’s corps from Virginia, and combined they outnumbered the Army of the Cumberland. In formation, Thomas was at the center, but after a series of missed communications he was forced to march his men all night to reach the exposed northern flank.  Explore multimedia from the series and navigate through past posts, as well as photos and articles from the Times archive.  By the night of Sept. 19, with Thomas’s forces in the north facing eastward, the Union had held its line on the first day of battle. The dense terrain made directing movements difficult. Still, Thomas had employed his divisions well and placed artillery effectively, never surrendering ground to Bragg and using counterattacks to deny Bragg any momentum. That evening Thomas requested reinforcements to form a new defensive line and set up breastworks. Thomas operated on a couple hours of sleep after none the previous night. Yet where Rosecrans was desperately nervous, Thomas was confident and still largely energetic.  The second day of the battle was more chaotic. As the fighting raged, riding south Thomas found a line of Confederate troops moving north behind the Union lines, a stunning development. At 11 a.m., probing the Union center Longstreet had found a gap left by a movement of troops by Gen. Thomas Wood at just the right moment and poured through, splitting the Union force and creating chaos as many Northerners began to flee en masse. As the Union right disintegrated, Rosecrans and his staff fled toward Chattanooga. Two of his three corps commanders followed. But Thomas remained.  Thomas moved to Snodgrass Ridge, a high ridge where he had stationed artillery. Men scattered from different units had created mass disorganization. The artillery Thomas had expected had also been taken by one of his own division commanders after men had begun to retreat, as had his ammunition train. Nevertheless, Thomas stayed anchored to the ridge to supervise its defense, recognizing that any retreat before nightfall would be catastrophic and could threaten the entire army. Improvising with men from the numerous brigades, he was the only face the men all recognized, and he maintained his calmness, reassuring the men and leading counterattacks in person amid intense firing, even once admonishing an officer to walk, not run, so as not to alarm the men.  The hill was repeatedly attacked as the rebels tried to break the Union line. By 1:45 p.m., reserves under Gordon Granger finally arrived. Never hearing from Rosecrans, Thomas moved forward on his own initiative. At first wanting to use the men to fill the dangerously exposed gap to his north, with an attack mounting on the ridge Thomas faced the dilemma of where to use the two brigades. He correctly decided to use both to repulse the attack, as the rebels came with an entire coordinated division and a lesser Union force likely would have crumbled.  As men were running low on ammunition, Thomas’s scouts began stripping ammo from the dead. An order from Rosecrans through his chief of staff, Gen. James Garfield (the future president who, watching Thomas on the hill, gave him his moniker the Rock of Chickamauga), to retreat also conveyed to Thomas that there would be no reinforcements or ammo. The Confederates attacked again at 3:30, gaining a foothold on the ridge before being pushed back with Thomas pulling his sword and exhorting his men that “this hill must be held at all hazards!” Years later soldiers recalled Thomas’s stoic, calm leadership on the field at virtually all moments and believed it helped settle his own men under terribly difficult circumstances.  At 5 p.m. Thomas decided finally to retreat. He took personal charge of the men and moved them forward, catching the Confederates by surprise and pushing them back. He then set to work to build a defensive line to protect his tired men. But Bragg didn’t attack the following day, his men also disorganized and tired.  Chickamauga would end up the second bloodiest battle of the war. The causalities were horrendous: 16,179, or 28 percent of the Union army were killed or wounded, approximately 18,000, or a quarter on the Confederate side. Bragg had almost succeeded in crushing the Union army. Thomas’s leadership was decisive in preventing the Union’s annihilation in the Western Theater.  In the aftermath of the battle, Thomas became a national hero. His leadership and preparations repeatedly frustrated the South from achieving a decisive victory. He was innovative and cool under the most perilous circumstances imaginable, leading and improvising to harsh tactical conditions. And his command showed enormous courage. There were few men alive at that time that held the administrative experience, extensive training, calmness of discipline and deliberateness to maintain the army’s position on the battlefield that day. It was one of the greatest displays of leadership during the entire war.  Follow Disunion at twitter.com/NYTcivilwar or join us on Facebook.  Mark Greenbaum is a writer and attorney in Washington.
The life of Gen. George Thomas, who saved the Union Army from disaster in one of the Civil War&#8217;s bloodiest battles.