After WWII Russia kept all the territory it had covered and became the USSR, These countries were not given a fair choice in the matter. When countries like Czechoslovakia and Hungary wanted their freedom the USSR reacted swiftly and very hard with soldiers and tanks to wipe out the opposition. Once the USSR collapsed these countries were own their own, for better or worse. Unfortunately old prejudices and hate came out with violent results. If this happened under USSR control they would have crushed the squabbling.
