Initially assigned to the defense of Confederate forts in Pensacola Bay, Florida, the 33rd was quickly transferred to duty in the Army of Tennessee, where it saw its first significant action at the Battle of Perryville. It went on to fight at Stone's River, Chickamauga, the Siege of Chattanooga, the Atlanta Campaign (including Ringgold Gap and Kennesaw Mountain), and the disastrous Franklin-Nashville Campaign in late 1864.