Final answer:
The Battle of Chickamauga is significant as it was the first major Civil War battle fought in Georgia, marking a critical turning point with Confederate forces forcing a Union retreat.
Step-by-step explanation:
The Battle of Chickamauga is a significant event in American Civil War history for a few reasons, but the most accurate answer to the question given is that it was the first major Civil War battle fought in Georgia. This battle was not the first Union victory, nor the deadliest to date at the time it occurred. While it was not the last Union incursion into the South either, it marked a critical point in the war as Major General William Rosencrans's mistake allowed Confederate General Braxton Bragg to force a Union retreat to Chattanooga.