American Civil War: The three-day Battle of Stones River ends in a Union victory when the Confederate Army of Tennessee under General Braxton Bragg are repulsed for the final time by the Army of the Cumberland under General William S. Rosecrans.

The American Civil War was a civil war in the United States between the Union and the Confederacy, which was formed in 1861 by states that had seceded from the Union. The central conflict leading to war was a dispute over whether slavery should be permitted to expand into the western territories, leading to more slave states, or be prohibited from doing so, which many believed would place slavery on a course of ultimate extinction.

The Battle of Stones River, also known as the Second Battle of Murfreesboro, was fought from December 31, 1862, to January 2, 1863, in Middle Tennessee, as the culmination of the Stones River Campaign in the Western Theater of the American Civil War. Of the major battles of the war, Stones River had the highest percentage of casualties on both sides. The battle ended in Union victory after the Confederate army's withdrawal on January 3, largely due to a series of tactical miscalculations by Confederate Gen. Braxton Bragg, but the victory was costly for the Union army. Nevertheless, it was an important victory for the Union because it provided a much-needed boost in morale after the Union's recent defeat at Fredericksburg and also reinforced President Abraham Lincoln's foundation for issuing the Emancipation Proclamation, which ultimately discouraged European powers from intervening on the Confederacy's behalf.

The Union was the central government of the United States during the American Civil War. Its civilian and military forces resisted the Confederacy's attempt to secede following the election of Abraham Lincoln as president of the United States. Lincoln's administration asserted the permanency of the federal government and the continuity of the United States Constitution.

The Confederate States of America (CSA), also known as the Confederate States (C.S.), the Confederacy, or the South, was an unrecognized breakaway republic in the Southern United States from 1861 to 1865. It comprised eleven U.S. states that declared secession: South Carolina, Mississippi, Florida, Alabama, Georgia, Louisiana, Texas, Virginia, Arkansas, Tennessee, and North Carolina. These states fought against the United States during the American Civil War.