The Holocaust did not take place as it is told in our current books/schools, so the question would rather be how was the real history of that time.

Most of the people in those former concentration camps (the 'FEMA' camps of our time) have not been killed by the Nazis, it would not even be possible with said gas as it was told to us. Many Polish people (Jews as well) have been killed by Russians...
the war itself was not started by Hitler as it is claimed by those who 'won' the war and so many people (French, Germans...) have been killed after the war was finished by those who wrote the history books.

The war was started in first place to hinder Hitler to free his country form the Vatican/London City-bankster system by implementing a free currency and the second reason was that the Germans themselves - in the opinion of some well-known people - had to be eliminated because of their genes/creativity/wisdom/real history. This last point did not change and there are so many German politics that do claim exactly this: 'I will not rest until the last german stopped existing.' This is no joke - the war is still going on.