Civil War - Uniform of Lt McGowan, 14th South Carolina Infantry

From a recent auction catalog. Notice that McGowan's choice of flag to illustrate his letter home is not the so-called Stars and Bars widely (mis)used today, but the original Stars and Bars.
[You must be registered and logged in to see this image.]

I didn't know about the flag. Amazing how you take things for granted

That is the Stars and Bars the other was a battle flag

The stars and bars introduced in 1861, amended in 1863, was also used by a number of regiments with the addition of a unit name, symbol or both.
The illustration is of the 1861 flag having seven stars, the stars increased when more states joined the confederacy.  
So you could argue that it performed the role of a battle flag, but it was never the official battle flag or the official national flag.
Here’s a page from a 1907 pamphlet authorized by the United Confederate Veterans showing the original 1861 version.

[You must be registered and logged in to see this image.]

Gerry Embleton
N. Carolina Cavalry Sgt. 1861
[You must be registered and logged in to see this image.]