When Germany decided to stretch it borders by attacking there was a clear chance that Germany would conwquer all of Poland, including areas that were assigned to the Soviets. As a result, the Soviet Union placed their troops on the former Russian territories of Poland, starting September 17, 1939.
From a Russian point of view, this was not invasion of another country, but taking control of the territories that were theirs before.
As this was managed in 2 days until they met in Brest, one can not even call this a war.
Russia in the same year started a campaign aganst Finland, to regain territories they lost prior.
Gandalf, so are you saying that Soviet Union acted right? Because, they really didn't have an permission to place their troops onto Poland's land, which were rightfully Poland's by the
Treaty of Riga.
Same goes to Finland, these areas, what Soviet Union conquered were rightfully Finland's by
Treaty of Tartu.
:ps: All the people, who say that don't discuss about History, Religion, War or Politics, because those are too touchy topics - Those are so touchy topics only when you don't hold enough information, don't listen to the other side and start to flame. These topics are really for the people, who can stay calm and really discuss. If you feel or main admin has made it clear for you, that you are not capable to discuss, but only argue, please stay out of topic, thank you.