toxicTom: The Holocaust of the Jews was rooted in the anti-semitism that goes way back. By Christian law, Jews weren't allowed to own land, even work other people's land - so they couldn't be farmers. The were not allowed to become craftsmen. So the only way to earn a living was becoming traders or bankers. Because they did not "work" they never became "of us" for the people. They were suspected to be lazy and greedy and there was hysteria about them sacrificing Christian children. They were ostracized and them condemned when they kept to themselves. And this
is rooted in religion. Even if Hitler was atheist (optinions differ), most of the Germans back then were "good Christians". And the hate also had its root in religion.
Jews were simply victims of politics - sacrificed to elevate the Nazi party. Used to unite the Average Joes against common "enemy" so to speak. Had there been no jews in Germany, the Nazis would have given the same treatment to some other religion, political party or just "non-aryans" in general. It was not really about christianity and was not prompted by christianity. I cant remember Hitler basing his actions on bible nor conquering rest of the world for God or whatever.
I am not certain if youve noticed, but the usual talk about antisemitism sounds awful similar to how many atheists treat say christianity even in this thread:
"I know many christians, but to me it seems like organized religions brings out the worst in people. Christianity has killed alot of civiliztions in the past, how can anyone belong to such group?" etc
-> this is called stereotyping. Just as jews are seen by some as greedy bankers, the very same way many stamp (for eample) christians of today by actions which happened hundreds if not close to two thousand years ago. Seriously just how silly is that?
----
but back to WW2:
So how about the soviets, would you blame their deathtoll on orthodox church or atheism? ....or could it be that was also just politics afterall?
WW2 and all the genocides would have happened regardless whether christianity existed or not. It would not have mattered if the whole Europe had still retained Norse or Roman faith or had indeed been totally atheist. Geopolitics would still be the same. And as long as geopolitics remain same - the wars over them will eventually flare up given "right" timing and fitting excuse.
(-> check Ukraine and Crimea)
If i need oil and you live on land that has oil - its very likely ill find a way to get it from you one way or the other. Depending on the circumstance it might not be nice way.
Wars are really all about geopolitics and resources - the wars, fights and crisis over these are simply clothed in religious and/or (rival) political appearance to make them easier for masses to swallow. Afterall if you need to instigate conflict to get things done, those are tools you need.
---
Concerning culture, well religions are not culture. They are part of culture. Might be even very huge and integral part - but they are not the "whole culture".
None of religions in existence were born from void to "empty culture". Christianity, islam, buddhism and all the rest were born inside existing cultures and got cultivated by them. Absorbed their base values from them. As easy example huge part of our holidays are actually pagan holidays, which were simply given christian makeup so that the then pagan finns and other converts would accept christianity more painlessly.
Buddhism in asia has alot of ancestor/spirit worhip going on, spells and fortune casting - none of which having anything to do with the Buddhism Buddha was teaching about. All the "supernatural" stuff is just leftovers from older nature religions before buddhism - which it then ofcourse absorbed.