 it upended that continent. It fundamentally changed things. World War I actually changed Europe more than World War II, though Hitler and the Nazis were far more destructive. The advances in munitions and aviation and long-range bombings was so much more destructive. But the death toll from World War I was so extensive and the war lasted so long, it upended social cohesion, it upended social status, it upended everything. Monarchies fell, heads rolled, revolutions started.