It's how finland was formed. Stalin thought it was a good idea to have a buffer state, and there it was, one buffer state came right up.
Stalin attempted to take Finland by force
Annexed
The red army did not do to well due to one of uncles joes numerous purges
Most of the officer core of the red army was purged meaning he had em shot / executed
But than again it may have been all a MIs understanding
The Russian army were passing through on there way to lap land for Christmas trees and the Finns MIs understood