Warspite1ORIGINAL: macgregor
I don't think the Finns would agree with this(nor the Poles -though they were in the Tsar's empire).ORIGINAL: composer99
Also, it was only once they had their deal with Hitler and the latter had begun the war that the Soviets began their own territorial expansion - which I should add was, until the Red Army marched into the Balkans and Central Europe in 1944-1945, limited to regaining Tsarist imperial territory. Stalin was a revanchist in that respect more than an expansionist. And, like Poland, Rumania and Hungary, which all had revanchist ambitions at the expense of their neighbours from 1938-1940, the USSR even had to cut a deal with Germany to make it happen.
Why? Finland was at one time part of Russia - I believe dating from Napoleonic times.
Just as the Soviets - still under Stalin - formed a defensive "Iron Curtain" on its western borders after WWII, so I believe Stalin wanted a similar buffer in the 1930`s/1940`s and parts of each of Finland, the Baltic States, Romania and Poland were to provide this. However, I do not think for a second that Stalin would have undertaken any of these actions had they not got the agreement - implicit or otherwise - of Germany - or even France/Britain had a deal been struck with them instead.