But not exclusively in the name of God.

Stalin did not use religion as a pretext for murder and genocide. Rwanda genocide was on tribal grounds, not religious.  Hitler's persecution of Slavs, Gypsies, homosexuals and the disabled, as well as Jews, was not on religious grounds.

It would appear that Hitler and Nazism was more influenced by the Nietsche idea of Ubermenschen (supermen, or master race) which came from an athiestic, evolutionary basis.