Southern Cross, CSA
Confederate States of America
Army of Tennessee Battle Flag
Description: Red field, blue cross of St. Andrew. Thirteen white stars on the cross. [X06]
This flag is often referred to as the "Battle Flag of the Confederacy". In actuality, the configuration shown above leads us to conclude that it was the Battle Flag of the Army of Tennessee which did not come into existence until 1863. The Battle Flag of Northern Virginia was quite similar, being more square with a fringe around the border and dated back to 1861.
The thirteen stars do not refer to the original thirteen states, but to the 13 supposed states of the Confederacy. Only eleven states seceded from the Union. Two border states, Kentucky and Missouri, declared themselves neutral.
Also see Flags of the Confederacy web site.