Finland is the home to many lakes, forests, and most metal bands in the world per capita. It is fair to assume that these are connected as folk melodies and instruments are a very common asset and nature an equally common source of inspiration and lyrical theme in Finnish metal music. I think the phenomenon has its roots in Finns being a very down-to-earth people with a close connection to nature, as only some decades ago most of the population lived in the countryside.
It is a common misconception that Finns are a very depressed people. Statistically they’re not. I think Finns just appreciate their personal space and only speak when they actually have something to say, and this might give the impression of a very reserved people.
When talking about Finnish music, most of it, maybe excluding hip hop which I know nothing about, does sound more depressive than the international hits. That’s why I think metal suits Finland very well. Finland’s black metal scene is also very interesting and deeper underground than that of the more commercially successful Norwegian cousins.