Racing is basically a national hobby in Finland. There’s not many other sports they can engage because the population density is sparse and the weather is well……. not good to say the least. So go-karting is very popular there (just under ice hockey, I believe) and with the roads covered in snow very often, the young drivers have a lot of extra exercises.
Also, apparently most of the country is very calm, stubborn and determined, a by-product of the mentality to stand their ground against foreign invaders all the time in their history plus their experience when they’re in conscription.
Lastly, F1 is not very popular in Finland. So only the best of the best can pass through instead of pay drivers supported by their people or a sponsor that viewed it as a hobby marketing opportunity and helped drivers that’s not necessarily the best but have connections.