The post-1918 borders which resurrected the Polish state only added to these traces because all the political parties in Germany perceived them as the result of an "ignominious peace" that favoured "the Poles" of all people. Although the neighbouring Republic was often disparagingly dismissed as a "seasonal state" by German politicians, it survived a whole series of seasons before being overrun by German and Soviet troops once again in 1939. The monstrosity of the German crimes that now began defies all descriptions: indeed these crimes have left deep scars in the minds of those involved, both victims, perpetrators and witnesses. Paradoxically, the numerous Polish forced labourers who were to be found in almost all the villages and towns in the Reich, led to more direct contacts between Germans and Poles than ever before. Emotionally, these ranged from hatred to love and left their own traces, of which Germans no longer wanted to be reminded in the years after 1945.

The story of the people and their associations who were expelled from the eastern regions of Germany in favour of the new Polish state was now more decisive in shaping German's ideas. For decades they complained of anti-Polish hardships, portrayed themselves as innocent victims and thus defined West German/Polish debates for many years. The Poles were the "expellees", i.e. the perpetrators, while there existed a "loud" silence about the causes of the expulsion. But it must also be said that it was often spontaneous, smaller, committed groups of expellees who sought contact with Poland. They were among the first to have personal exchanges with their neighbours after the war, often on many occasions. This undoubtedly applies even more to many of the 2,000,000 Polish immigrants who were able to communicate in both languages and travelled a lot "between the two worlds".

Nevertheless, in the West German 'economic miracle' years, the central and eastern parts of Europe remained a generally misunderstood part of the continent, situated beyond the "Iron Curtain" and marked by poverty, while people themselves were only too keen to forget the period before 1945. Since Germans also wanted to forget what they had done in and with Poland, this fostered the preservation of old "mental scars". At the same time the SED in East Germany (the GDR) blustered about the "Oder-Neisse peace border" and their "Polish brothers". Occasionally they permitted visa-free travel, which also allowed some of their citizens an insight into a country which enjoyed greater cultural and political freedoms than those back home. Apart from the tireless work of individual translators like Karl Dedecius, who tried to bring literary "traces" from Poland to the educated classes in Germans, it was above all mass media highlights that broke through the gaps in this continent of ignorance and half-knowledge. First and foremost was the US television series "Holocaust", which was broadcast on German television in the 1970s. Here, and in many other films, Poland was primarily seen as a place where Jews were exterminated in ghettos and camps (for which "Auschwitz" has become a symbol), while the fate of non-Jewish Poles under German occupation barely played a role. This is made clear, for example, by the "Warsaw Uprising": for a long time Germans automatically thought of it in terms of the 1943 ghetto uprising, while the non-Jewish uprising of 1944, which led to the complete destruction of the city by the Germans and the death of over 200,000 people, was barely known at all. In view of this partial or total ignorance it is hardly surprising that sloppy journalists in Germany and elsewhere refer to "Polish concentration camps", which regularly and rightly provokes outrage in Poland. They were, of course "German concentration camps", albeit set up on stolen Polish soil. This outrage in turn has repercussions in the minds of Germans, who now believe that their Polish neighbours are not only hypersensitive but also mega nationalistic – which creates new traces and new images.