Stalin was evil and would kill you.
Hitler was evil and would kill you.
So which side were the good guys on? The average Soviet soldier didn’t really start fighting until Hitler had made it apparent that he intended to kill them all either way. The odds that Stalin would kill them started looking more acceptable.
After the news arrived back (via non-official reliable sources) that most everyone who had surrendered in the summer of 1941 was dead and civilians were being liquidated, the Russians accepted death and began to take a real stand.
“So which side were the good guys on?”
Eastern Europeans liked to say that neither was good, but one was worse (Stalin). The casualties of 1941 followed on the heels of the Soviet Katyn massacre; this actually helped rally many who might have remained neutral to fear the Soviets much more than they feared Nazism.
The legacy of the Nazis will always include the evil they did, and should also note that nobody had ever unified so much of Europe against a common enemy before.