Holy Wars

To be considered a Holy War, a conflict must achieve a religious goal, be authorized by a religious leader, or offer participants a spiritual reward. Holy Wars, which mobilize to subjugate heretics, reclaim religious lands, and avenge blasphemous acts include:

Callously, Adolf Hitler wrote in Mein Kampf:

So glaube ich heute im Sinne des allmächtigen Schöpfers zu handeln: Indem ich mich des Juden erwehre, kämpfe ich für das Werk des Herrn.

While not a Holy War, religious beliefs influenced the terrible events that transpired during WWII, including the holocaust. The loathsome sentiment of Martin Luther's 1543 antisemitic work On the Jews and Their Lies is echoed in that Mein Kampf passage:

So today I believe that I am acting in accordance with the will of the Almighty Creator: by resisting the Jew, I am fighting for the Lord's work.