In both his 1872 letter to flag historian Admiral George Henry Preble and his 1878 memoirs, Joseph E. Johnston recollected that he had ordered that the battle flag of the Army of Northern Virginia be made in three sizes: 4 feet square for infantry, 3 feet square for artillery, and 2.5 feet square for cavalry. While the documentary and inductive evidence relating to the battle flags that General Beauregard instituted in the Confederate Army of the Mississippi and the Department of South Carolina, Georgia, and Florida suggests that this had indeed been the intent of the conference held at Centreville in September of 1861, the surviving flags from the Army of Northern Virginia fail to indicate that this policy was ever fully implemented.
In partial support of the policy, it should be noted that, while there are no surviving artillery-sized (i.e. 3 foot square size) battle flags of the 1861 silk issue, artillery-sized battery flags do survive as variants for both the 2nd bunting Richmond Depot pattern (with orange borders) and in the 3rd bunting Richmond Depot pattern (with white borders). Moreover, it is known that four battery flags were delivered to the Washington Artillery on 2 December 1862 that conform to the artillery size, i.e. they are basically 36″ square.
However, despite this issue, most of the surviving battle flags of batteries and artillery battalions of the Army of Northern Virginia are in fact infantry size (4 foot square). These include a few battery flags with both orange borders and a host of battery flags with white borders. The latter includes a group from the 2nd Corps artillery that were additionally decorated with battle honors.
While a few artillery size battle flags survive conforming to both the 2nd and the 3rd bunting patterns, NO cavalry flags agreeing with the proposed 2.5 foot square dimensions survive for either the silk issues or the 1st, 2nd, or 3rd bunting issues of battle flags from the Richmond Depot. To the contrary, the cavalry flags that do survive [including one silk battle flag from the issue of 13 December 1861 (6th Virginia Cavalry- with a YELLOW pole sleeve), one orange bordered 2nd issue bunting battle flag (7th Virginia Cavalry), and a host of cavalry battle flags conforming to the 3rd bunting issue] which are all basically 48″ square.
There have been several suggestions proposed to explain this inconsistency between the proposed policy and the actual practice. Upon reflection, the 2.5 foot square flags may have been determined to be too small. (And, indeed, at least three cavalry flags do survive that are essentially 42″ square.) A more likely alternative suggests that the requisitioning officers simply asked for a “battle flag” without specifying size, and the supply officers simply furnished what was on hand– an infantry battle flag.
Howard M. Madaus, 17 February 2000