The short answer:
a) Yes, they have an origin in 9-10th century archaeological finds from Sweden.
b) Without the fur and with metal-decorated bands, men buried at Birka. With the fur, you're probably looking at the Rus.
The first question is "what sort of Norse-person are you?" these caps are a masculine item of clothing, so you mightn't want to wear them if you're a woman. If you're the sort of Norseman who thinks they'd be more 'Eastern' (such as hanging out at the harbour at Birka in modern day Sweden, or further east and trading with the Rus) then the little dome-cap style has some evidence for its' use. It's evidence, though, is based on the metal trims that decorated the brim. There are educated guesses about how they were made (eg. http://www.cs.vassar.edu/~capriest/manshat.html)
but I don't believe they've found a near-complete one yet. The Birka textiles are dated 9-10th centuries.
Inga Haegg in her article in "Birka II:2" (which is where the quote that Rae posted originally came from) doesn't mention a fur brim though.
Where the fur brim comes from seems to be Rus clothing, and it seems (from looking at Sofya la Rus' pages below) that they were worn by both men and women between the 9-13th c.:
(scroll down to 'hats', discusses menswear.)
Svyatoslav II's Izbornik (1073) shows a domed cap with what looks to be a fur brim: http://gioconda.livejournal.com/302996.html
(third on the right, top row.)
(seems to imply that women wore fur-brimmed hats later in the middle ages).
I don't know about Mongol clothing, so can't really comment. :)
Hope that helps,
--- In SCA-Garb@yahoogroups.com, "Tami" <tami.kat@...> wrote:
> Question one - are these period and what period do they fit in?
> Question two - what group wore these hats? Vikings? Mongolians?