>>2501359>VItale BRAManiHuh, just noticed that
Also mountain warfare. Historically people tried to avoid fighting in mountains because they're fucking nasty environments and even a small group of people can hold off a superior force just by throwing rocks down the mountain. The Nazis briefly considered annexing Switzerland into the Reich, but decided the estimated losses were unacceptable.
Since hand grenades, carbines, mortars, and aircraft were invented, mountains were opened up as combat terrain, so the technologies of mountaineering developed. Post WW1 a lot of ex-mountain troops from Germany, Austria, and Italy had picked up the bug and continued developing tools and techniques.