groups like the mongols easily took rus lands and burned kiev because of their protection against the mentioned problems. Steppe horses and soldiers were good in the cold, their tools were working just fine, and their raiding of cities like kiev made it easy to just not need supply lines.
Mongol horses eat all the food in an area, they have to remain mobile.
They were easily defeated (2nd time around) with area and food denial methods like castles.
