The Battle of Chattanooga began when Union forces, primarily commanded by General Ulysses S. Grant, mounted a counter-offensive against the Confederate army, which had besieged Chattanooga, Tennessee. Following a series of battles in the summer of 1863, the Union achieved a critical strategic victory at the Battle of Gettysburg, which bolstered its morale but left continued challenges in the western theater. Chattanooga was pivotal for the Union, acting as a significant transportation hub crucial to moving troops and supplies. After months of hardship, the Union troops were reinforced, allowing them to prepare an offensive against General Braxton Bragg’s Confederate forces, who were attempting to maintain control over the city.The Union's counter-offensive began to materialize on this day, focusing on a coordinated attack. Grant employed a tactical approach, utilizing his newly reinforced divisions effectively to exploit weaknesses in the Confederate lines. This military operation aimed not only to lift the siege but also to pave the way for the Union's advance into Georgia, setting the stage for further victories in the Deep South. The engagement would see intense fighting, characterized by aggressive assaults and tactical maneuvers, ultimately determining the fate of Chattanooga as a Union stronghold.In the days that followed, the situational dynamics shifted, with both Union and Confederate forces experiencing significant losses. The Union's successful operations would culminate in the decisive victory at the Battle of Lookout Mountain and Missionary Ridge, leading to the eventual expulsion of Confederate forces from Chattanooga altogether. This moment marked a crucial turning point in the Western Theater of the American Civil War, signaling the beginning of the Union’s concerted efforts to penetrate deeper into Confederate territory.