The red shirt is a bit weird....
That is Hollywood again. (sigh)
He is wearing a “Battle Shirt”, designed to be worn by itself. NOT under a tunic.
And NOT accurate, as most of the series wasn’t.
BOTH sides "practically decided upon " BLUE or GRAY as "outer garments" because of BOTH sides shooting AT their OWN troops in the early days of the WBTS. SOME units (like Berdan's Sharpshooters, however, chose to "do their own thing" until war's end.)
free dixie,sw
the prison factory had no dye to dye them, so it was "left up to the troops in the field" to "deal with the problem". (most men chose to "dye" the white uniforms with nutshells and/or boiling them in muddy water.)
the "muddy-colored uniforms" turned out to be EFFECTIVE camouflage, according to some wartime letters!
free dixie,sw
I believe it was A.P. Hill who always wore a red shirt into battle. It became a bit of a trademark for him