Finnish national animal is a bear that had always an important role in Finnish mythology and ancient believes. Bear (Karhu) was considered to be the owner of the forrest, maybe the forrest itself. Then nature was and in a way still is the core of the Finnish mind in a way.
For example most of the Finnish family names come from nature related words: Joki = river, Kallio = crag, Niitty = field. (In comparison in Germany most of the last names come from occupational words: Müller = a miller, Schuhmacher = shoemaker.)
Also what a bear indicates fits quite well the Finnish personality with certain plainness and rawness. In addition it's both feminine and masculine at the same time, like our society. And finally bears also sleep through the whole winter and wake up in the spring to the first beams of light, haha.
So, this long story sums up pretty well why I just love Karhu beer brand and it's logo. It holds the truth about us Finns. :)