Okay so IANAL but I do work for the Finnish government and I have to deal with the Police Board every once in a while.

The police in Finland are a national organization (cities or provinces don't have their own police, they are all under the same organization) and they have jurisdiction over a lot of permit and license matters, like residence permits, raffles and lotteries, and in this case the raising of funds. This side of the police administration is taken care of by the Police Board instead of any local police department. They answer directly to the Ministry of the Interior. They do not investigate crimes or prosecute people, the Board is a purely administrative organ. In other words Wikipedia is not under criminal investigation, though the Board could refer this to a police department in Finland to see what they make of this, since the police departments are responsible for actual investigation. Requesting a statement from an entity that may be raising funds is a pretty regular bureaucratic procedure, in a sense.

The problem here is not that the police board have "too much spare time" (my personal experience is the exact opposite, and reading the request, it would have been written within an hour or two by a junior official), or that they are petty power-hungry tyrants out to suppress the freedom of information, it's that their job is to interpret Finnish law and the Finnish law when it comes to fundraising is terrible and about two decades out of date. Hopefully this will get enough media attention in Finland to start a political discussion that leads to a proper reform of the law.

I doubt they expect the police will be able to initiate anything against Wikipedia, but they would be negligent in their duty as public officers to not do anything about the issue once it came to their attention.

I find it unlikely that Kyösti Kallio declared war on Russia after Barbarossa began, since Kallio left office in 1940 and Barbarossa began in June 1941. However, my credentials aren't quite as good: my granduncle Akseli Anttila was merely a General of the Red Army who had left to Russia during the Civil War. He was also the Defence Minister of Kuusinen's puppet government.

Churchill certainly sang Finland's praises during the Winter War, but the planned military aid operation via Norway never materialized, only some volunteers from Sweden and a few Allied countries, primarily the UK. This goodwill disappeared after a Finland lead by President Risto Ryti accepted German trade and soldiers into the country during the so-called interwar period, which culminated in German airplanes using Finland as a landing area in the early phases of Barbarossa in late June 1941. By this time, Northern Finland was housing German soldiers, who had the frontlines in the Petsamo/Murmansk direction during Barbarossa. This obvious pact lead to the Soviet Union doing the logical thing and bombing Finnish cities and installations, which lead to declarations of war.

But you can certainly say Finland was screwed both ways several times, what with first having to deal with the Soviet Union enabled by German consent, then the Soviet Union while working with the Germans, and then finally having to deal with the stragglers of the German forces after signing a peace deal with the Soviets - a deal that was struck in the nick of time, when the Finnish forces presented just enough resistance so that the Soviets couldn't bother and preferred to focus on Central Europe instead of Finland.