In Europe Basicly, it's the frontlines who decide the borders, The Germans did'nt aceppt to retreat from france, since they fight for those lands, at same way, the Entente didn't aceppt the German rule over the balkans. In Africa the regiona that sucessfully revolt proclaim independence, and the germans lost almost all their military during the great war, so the can't invade all British remaind colonial empire. Japan Imperial ambitions consolited since the European power are wekened they can't stop the Japanese Empire. Almost everything was decided based in how far they can conquered till achive a Stelamate.