A view of a smoothbore bronze cannon at the Chickamuga Civil War battlefield. The Battle of Chickamauga was fought between September 18-20, 1863, between the Union Army commanded by Major General William Rosecrans, and the Confederate Army commanded by General Braxton Bragg. The Battle was a major defeat for the Union forces, with more than 35,000 troops killed, wounded or declared missing/captured from both sides.