Thinking about “History is written by the victors” makes you figure it’s worthwhile to listen to what the losers of history had to say to determine the historical accuracy. When it comes to Hitler, we tend to portray him the way he portrayed himself. We aren’t making it up, he really thought that:
The victor will not be asked afterward whether he told the truth or not. In starting and waging a war it is not right that matters, but victory. Close your hearts to pity. Act brutally. Eighty-million people must obtain what is their right. The strong is right. Be harsh and remorseless. Be steeled against all signs of compassion. Whoever has pondered over this world order knows that its meaning lies in the success of the best, by means of force.
Adolf Hitler to the Wermacht soldiers in August 22, 1939. Shortly before the invasion of Poland and start of WWII.
The Rise and Fall of the Third Reich, Chapter 15