>>510911260
They had to invade all those countries because their economy ran on plunder, and they saw the slavs as backwards peasants unfit to rule themselves, so they thought achieving autarky at their expense was fair game.
They also couldn't stop while they were winning because the Soviet Union had to be annihilated eventually, or they would be the ones getting invaded.
>>510912692
They slaughtered all those people in Eastern Europe as a matter of competition for resources on a continental scale.