The partition of Europe between the two victors of WW2 (USA and USSR) was part of the peace, not a state of war. The cold war wasn't a war inside Europe but between two rival superpowers; the Yugoslavia war wasn't one between EU countries but a civil war result of a change in external conditions.
And Stalin continued to take territory even later, moving into East Germany, Czechoslovakia, etc . Continuing with military pressure over the later years.