And also maybe 80% of the blame for starting the war was Russia's too. The war started when Germany invaded Poland, knowing they had nothing to worry about Russia, because they had agreed with Russia to divide Poland between themselves. After Russia entered the war (when Germany surprise-attacked them), Russia received support from the US, who basically financed the war for the russians. The war ended, and Russia -who was an impoverished state before the war- ended as a nuclear superpower who controlled half of Europe. So they started the war, ended the war, and gained more than anyone from the war.