>>512579297
They did that because they were lazy idiots, too weak to fight for Africa with British Empire or the French, so they decided to engage in colonialism in Europe and steal land next to them (once with paved roads and railroad tracks), but it needed some propaganda pitch, so they decided to call everyone east of them subhumans that occupy lands that is needed for the German poeple (for sometrhing)..
Their propaganda arch-nemesis were Judeo-Bolsheviks, but they didn't have trouble siding with them to attack others.