The first time I saw a picture of a soldier in the Civil War–I forget it he was Union or Confederate–the cap looked cylindrical, like a French officer’s cap. over time, however, I noted that the caps’ tops are tilted forward, and at first I assumed it was because the cap was old. Is the Civil War soldier’s cap flat-topped, or is the top tipped forward?
The Civil War kepi’s top is tilted forward. I think there was other CW headgear that was flat on to though.
You have to bear in mind that the uniforms weren’t. Uniform, that is. I remember seeing a book on Civil War military goods. I think the problem was that states had slightly different uniforms. So you might see all kinds of variations in the hats, coats, pants, etc.