Nazi Germany’s death camps were copied directly from the Soviet system of Gulags. “The Protocols of the Elders of Zion” was a Russian fraud adopted by the Nazis to promulgate hatred of Jews. There are more than just parallels. There are direct links between the Nazis and the Soviets.
Also I find it curious that Stalin, basically let Hitler waltz into the parts of the Soviet Union, where the majority of their Jews lived.
It’s as if he knew Hitler would take care of his own “Jewish Problem” for him.
You might be interested in a period essay called “Slave Labor in Soviet Russia” published in English in 1937. It was written by a German Nazi who died at the end of the war, a certain Dr. Hermann Greife, and offers firm proof the Nazis knew exactly what the S*viets were doing. You just have to wade through a heavy dose of Nazi propaganda along the way.