After the disintegration of the Soviet Union, why didn't Germany demand the recovery of East Prussia? To put it simply, there are several factors. First, Germany has subjectively given up the old East Prussia. As we all know, the end of World War II was accompanied by inter-ethnic migration and population exchange. After the Battle of East Prussia, the Soviet Red Army entered East Prussia, and the local German residents moved away on a large scale. At the same time, Russians, Belarusians and Ukrainians also moved here on a large scale. What followed was the change of local ethnic composition and the change of city place names. By the time the Soviet Union collapsed, the local population structure had undergone fundamental changes. Germany has lost its demographic and cultural basis for recovering old East Prussia. In addition, after World War II, Germany was divided into East Germany and West Germany. Both East Germany and Poland belong to the Soviet camp. Under the mediation of the Soviet Union, East Germany had long since given up its pursuit of East Prussia and recognized the Bode border. West Germany was tough at first, but after the Brandt government promoted "New Orientalism" in the 1970s, it gradually gave up its claim to "Oriental Land". At this point, by the middle of the Cold War in the 1970s, both East Germany and West Germany had subjectively abandoned the old East Prussia. Therefore, even if 1990 was unified, it did not change the policies and roads formulated before.