We're so disappointed the website selling this hat chose to model it on a log, rather than on a person. It means we can only imagine what it would look like on a human head... and we don't know about you, but we're imagining it would make its wearer look a little bit like a caricature of a viking.
We guess that provides us with one answer to the question in the title, at least: you would wear it to go adventuring in a longship in the 10th century. Or, we suppose, if you must insist on wearing it in modern times, anywhere with a cold climate would do: it might look a little bit odd, but all that goat hair has to at least be warm, don't you think?
What DO you think of this? Where would you wear it, assuming you WOULD wear it?