In kindergartens and schools in Norway, it is quite common to have something called a "nissedag" at some point during advent. "Dag" means "day", and a "nisse" is a mythical creature thought to live at farms. They would do some sort of unspecified good deeds (at least if they were kept happy, by giving them some rice pudding from time to time), but generally be very elusive and only move about at night (a common trait among mythical creatures, as they would otherwise just be creatures). I guess you could say the nisse is more or less the Scandinavian version of the brownie.

A nisse is traditionally seen as smaller than a human, I'd say about half to one third the size of grown person, and they are usually pictured with white beards, and wearing traditional clothing such as a knitted sweater, plus fours (made from coarse grey wool, not tweed), woolen stockings and a red hat (after brushing up on my hat related vocabulary at wikipedia, I'd say it's similar to a Phrygian cap), so essentially old fashioned skiing gear. And this is precisely what people will dress up like at a nissedag (though in general you would get away with putting on a red shirt). But why this weird tradition of dressing up as mythical creatures, and how is this releated to Christmas?

The truth is that I have no idea how this came about, but I'd bet it has something to do with the Norwegian word for Santa Claus being "Julenissen", meaning "The Christmas nisse". In any case, there is a quite strong connection between Christmas and the traditional nisse. I don't think it's ever been a tradition to say that the nisse brings presents, or has any other specific role related to Christmas, but the nisse is still a very popular motif for Christmas cards (see Google Images: Nisse). Also, one is supposed to put out a bowl of rice pudding for the nisse on Christmas eve. This is the main topic of the Norwegian Christmas carol "På låven sitter nissen":

På låven sitter nissen med sin julegrøt,
så god og søt, så god og søt.
Han nikker, og han smiler, og han er så glad,
for julegrøten vil han gjerne ha.
[...]

English, courtesy of me:

The nisse sits in the barn with his Christmas rice pudding,
so good and sweet, so good and sweet,
He's nodding and he's smiling and he's very happy,
because he really likes Christmas rice pudding.
[...]

I think it's becoming increasingly more common to go to a nissedag dressed up in some sort of pre-made, Coca Cola inspired Santa Claus costume, but the last time I attended a nissedag (which must be something like 13 years ago), the majority of those who could be bothered dressing up at all was still going for the traditional look. Also, I mentioned earlier that an adult will often dress up as Santa and hand out candy at a juletrefest. It is also quite common to go for the traditional nisse look in this situation, sometimes complete with cross country ski shoes for good measure (the idea probably being that anything related to snow must surely give extra Christmas points).

-Tor Nordam