Final answer:
The Battle of Chickamauga was the bloodiest two days of the Civil War and a great victory for the South, causing the Union forces to retreat into Chattanooga.
Step-by-step explanation:
The battle that is said to be the bloodiest two days of the Civil War and a great victory for the South, causing the Union forces to retreat into Chattanooga, is the Battle of Chickamauga. It took place from September 19-20, 1863, in Georgia. The Confederate Army, led by General Braxton Bragg, successfully defeated the Union Army, led by General William Rosecrans.
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