What are some ideologies that could develop something similar to Nazi Lebensraum and Generalplan Ost or even attempt it ? Two candidates, I could see would be Greater Israel or a Hindu Nationalist Akhand Bharat. Given the artificial nature of the majority of Sub-Saharan Africa, I can't see many possible candidates there. Maybe a more extreme Megali Idea attempted to remove the Slavs and Turks from Byzantium's 1066 borders ?Following Adolf Hitler's rise to power, Lebensraum became an ideological principle of Nazism and provided justification for the German territorial expansion into Central and Eastern Europe.[5] The Nazi policy Generalplan Ost (lit. 'Master Plan for the East') was based on its tenets. It stipulated that Germany required a Lebensraum necessary for its survival and that most of the populations of Central and Eastern Europe would have to be removed permanently (either through mass deportation to Siberia, extermination, or enslavement), including Polish, Ukrainian, Russian, Czech, and other Slavic nations considered non-Aryan. The Nazi government aimed at repopulating these lands with Germanic colonists in the name of Lebensraum during and following World War II.
Lebensraum - Wikipedia
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