You might reasonably assume that America has always worn long-sleeve shirts cut much like the ones it wears today, except made in fabrics like muslin and linsey-woolsey.
Not a bit. The original Great American Shirt (pre-Revolutionary days to ca. 1875), was cut extra-long, with extra-full sleeves that had lots of gathers.
It came in two versions: (A) ruffled collar and cuffs, gentleman-style (Ben. Franklin, George Washington, etc.); (B) plain-collar, button-cuff working-man style (Sam Adams on Boston Lager label).
What you see here is a Civil War Cavalry issue of Version A. It gives a man freedom to move. When he catches sight of himself, he just naturally thinks, “Hmm, looking good,” and so do other people.
Gentlemen, you know the situation; these are the times for all real American men to put on their shirts again.
The Great American Shirt (No. 2345). In comfortable, lightweight cotton, as described, with lots of gathers at front and back yoke too.
Men's sizes: S, M, L, XL, XXL.
Length ranges from 31 1/2” to 33 1/2”. Varies by size.
Colors: Natural, Light Blue, Indigo.
Care Instructions: Machine Washable.