Anti-Slavism was the movement that existed throughout World War II, parallel with the Anti-Semitism. It was directed against the people of Slavic origin (such as Russians, Poles, Serbs, Czechs, Slovaks, Ukrainians, etc).
In his book, Mein Kampf, Hitler refers to them as "inferior", using the word 'Slav' as 'slave'. He thought that the peoples of this origin should 'remain' the slaves as they were througout the centuries. This was likely a reference to the Ottoman Empire, Austro-Hungary, where the Slavs were numerous but not empowered and rather exploited instead.
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