I don't have any real sources on hand. It was mostly finding out that the winter war wasn't just hte Soviets being big meanies. During the part of the Russian Civil War in Finland the Whites, along with about 10,000 Germans, slaughtered the Reds and took over the country. Eventualyl WWII comes around, Stalin's like "Hey, the Nazis are going to invade Leningrad. We need some land on this penninsula to set up defenses and we need you to take down your forts here. We'll trade you twice as much land in return. The Finnish government was going to agree with it then some of those White generals left over from the Russian Empire were like "Nah, fuck you and fuck your city." So Stalin was like "We weren't asking" and invaded Finland, took a buffer zone around Leningrad, and dismantled the Finnish forts. About a year later the Nazis invaded just like everyone involved knew they were going to, and the Finns were like "Yeah, sure, we'll go lay siege to Leningrad. I mean get our territory back." So they invaded the Soviet Union alongside the Nazis, killed about a million Soviet Civilians during the siege of Leningrad, then eventually got their asses kicked when things turned around on the Nazis.

So sweet, innocent Finland being invaded by the big bad Soviets is bullshit. It's like one eighth of the entire story, framed so the guys who collaborated with the Nazis look like the goodguys.

Apparently their air force was the first euro military force to use the swastika back in the late 20s or early 30s