In the summer of 1863, a divided nation waited for news. The American Civil War was 2 years old and showed no signs of ending soon. In the east, a Confederate army under Robert E. Lee was poised to invade Pennsylvania, provoking apprehension and not a little outright panic. Along the Mississippi, the Rebel fortress of Vicksburg was encircled by Gen. Ulysses S. Grant, and Southerners feared the worst.
Yet in Middle Tennessee, all seemed quiet. The Federals under Gen. William Starke Rosecrans held Nashville and Murfreesboro but little else. Arrayed along the Highland Rim, Confederate Gen. Braxton Bragg's Army of Tennessee stood ready to meet the Unionists should they march, but Bragg's army was much smaller than Rosecrans,' and battle would be a risky proposition.
Rosecrans was under great pressure. Sensing that this critical year could decide the war, Lincoln wanted every man in action. Rosecrans, who had superiority in all arms save cavalry, felt he needed more mounted men before he could successfully trap and defeat his opponent. Rosecrans didn't want to merely drive the Rebels out of Tennessee, he wanted to destroy the Confederate army outright. By the end of June, his meticulous preparations ready and his plans carefully laid, Rosecrans began a movement which came close to doing exactly that.
Bragg's supply was tied to the railroad, with his base at Tullahoma. His army held a series of gaps in the Rim, terrain easily defended by his smaller numbers. Confederates were stationed at Wartrace and Shelbyville, behind Bell Buckle, Liberty, and Hoover's gaps. Bragg intended to use the terrain as a strength multiplier, forcing Rosecrans to attack him in unfavorable circumstances. Rosecrans had no intention of complying.
Eyeing his maps, Rosecrans's attention turned to the town of Manchester. If some Federals feinted toward Shelbyville, fixing Bragg's attention on Bell Buckle and Liberty Gaps, then he could march a corps around Bragg's right flank and seize Manchester. Another corps, commanded by his most trusted subordinate, Gen.George Thomas, would move quickly through Hoover's Gap and open a direct road to Manchester, down which the bulk of the Union army would rush.
From there, the Federals could strike westward to seize Tullahoma and trap Bragg. Even if Bragg tumbled to Union intentions quickly, he would still have to reposition his own army to face the new threat.
On the warm, rainy afternoon of June 26, Rosecrans set things in motion. Union cavalry moved south toward Bell Buckle Gap. Union infantry marched to Liberty Gap. Col. John T. Wilder's brigade of mounted infantry, equipped with seven-shot Spenser repeating rifles, dashed forward to seize control of Hoover's Gap.
Wilder's men succeeded brilliantly, driving off Rebel defenders and beating back a counterattack with their rapid fire. Henceforth they bore the sobriquet of "Lightning Brigade."
In a year marked by drought, the beginning of the Union movement coincided with a solid week of rain, turning roads to mire and greatly slowing marching columns. Rosecrans was already gambling that the Confederates would fail to react quickly while his army was divided, and now, with everything slowed, that gamble grew larger. Fortunately for the Federals, Braxton Bragg's Army of Tennessee had its own problems.
Damaged relationships between Bragg and his senior subordinates over the unhappy Kentucky Campaign the year before meant that the Army of Tennessee was barely functioning, suffering from poor morale and recalcitrant senior leadership. Bragg was by nature aggressive, and once he detected Rosecrans's movements, he turned immediately to the idea of a counter-attack. By sending the bulk of his army through Guy's Gap, Bragg reasoned that he could fall on a portion of the Yankee force. This plan failed when his senior officers objected to the risk. Instead, Bragg fell back to Tullahoma and prepared to defend his base.
By June 29, it looked to both sides as if there would be a major battle at Tullahoma. That changed the next day, when Bragg abruptly decided that retreat was his only option. He was badly outnumbered, and a Union raid on Decherd, Tenn., convinced the Rebel commander that he was vulnerable to being outflanked again. On July 2, Bragg ordered his army back to Chattanooga, surrendering all of Middle Tennessee.
Rosecrans was ebullient, though he soon discovered that his army's triumph was overshadowed by Lee's retreat from Gettysburg and Grant's capture of Vicksburg, both of which occurred on July 4. Further, as Lincoln noted, Bragg's army escaped to fight another day.
Historian Dave Powell has written two books on the Chickamauga campaign, as well as numerous smaller articles and essays. For more information, visit chattanoogahistoricalassoc.org.