Backward.
Hitler's excuse to the West was that his people needed land because they were unconscionably crowded into the narrow borders imposed on them by the victors of WWI.
At home, his argument was restoring the original boundaries of the German Empire, to undo the humiliation of Versailles and to reassert German greatness.
And that was his motivation - Hitler wasn't driven by a desire for natural resources, he was driven by his ideological demons.
I think you’re largely correct in your assessment of Hitler, but the General Staff of the German Army was mindful of the importance of oil. This is why they shifted the bulk of their mobile forces to the caucuses region when they should have seized Moscow & Leningrad.
As to restoration of the German Empire, there were ethnic Germans living in settlements all through eastern & central europe, all the way to the Volga River. Remanents of communities that got their start during the medievel period when dynastic considerations were more important than ethnicity.
A friend of mine is German. His family traces its roots to the Harz Mountains in Saxony, I believe. Further back his ancestors were ‘guests’ of the Hungarian King somewhere in the Kingdom of Hungary. Taking Hitler’s dream of uniting ethnic Germans under the German State, & his military’s practical need to have oil (Romania), you got what you got.