When I made my 14th century Russian garb (lovely period, btw. Quite comfortable, and warm) I needed, of course some kind of headwear. Preferably one which wasn't commonly seen...this mostly left a tall kolpak. I really don't feel like writing an article--when Sofya la Rus has already done so, and better than I can. So go read HERE...I'll wait.
Well, they seem to have "typically" been made of a stiffened felt--not an option for me, sadly; I don't have the materials to do so. So I went with a logical variation--using birch bark as a stiffener. I figured "birch is common in Russia, and was used for some things, so why not" (I seem to recall a collar stiffened with thin leather or bark).
