After a few years of fighting, the Red Army drove the German forces out of the USSR and crossed into Poland from the rest of Central and Eastern Europe.

Sociologist Tadeusz Piotrowski argues that both occupying powers were hostile to the existence of Poland's sovereignty, people, and the culture and aimed to destroy them.

[2] Before Operation Barbarossa, Germany and the Soviet Union coordinated their Poland-related policies, most visibly in the four Gestapo–NKVD conferences, where the occupiers discussed their plans to deal with the Polish resistance movement.

[11][12] Non-German population on the occupied lands were subject to forced resettlement, Germanization, economic exploitation, and slow but progressive extermination.

[11][12][13] A small strip of land, about 700 square kilometres (270 sq mi) with 200,000 inhabitants[8] that had been part of Czechoslovakia before 1938, was ceded by Germany to its ally, Slovakia.

The Soviets gained recognition of their pre-1941 annexations of Polish territory; as compensation, substantial portions of eastern Germany were ceded to Poland, whose borders were significantly shifted westwards.

[10][26] The goal of the occupation was to turn the former territory of Poland into ethnically German "living space", by deporting and exterminating the non-German population, or relegating it to the status of slave laborers.

[34] The Slavic inhabitants of those lands would be eliminated as the result of genocidal policies;[32][35] and the survivors would be resettled further east, in less hospitable areas of Eurasia, beyond the Ural Mountains, such as Siberia.

Jews were drafted to repair war damage as early as October, with women and children 12 or older required to work; shifts could take half a day and with little compensation.

[56][57] The decrees required Poles to wear identifying purple P's on their clothing, made them subject to a curfew, and banned them from using public transportation as well as many German "cultural life" centres and "places of amusement" (this included churches and restaurants).

[10] A network of Nazi concentration camps were established on German-controlled territories, many of them in occupied Poland, including one of the largest and most infamous, Auschwitz (Oświęcim).

The ghetto system was unsustainable, as by the end of 1941 the Jews had no savings left to pay the SS for food deliveries and no chance to earn their own keep.

[68] At 20 January 1942 Wannsee Conference, held near Berlin, new plans were outlined for the total genocide of the Jews, known as the "Final Solution of the Jewish Question".

[73] Proscription lists (Sonderfahndungsbuch Polen), prepared before the war started, identified more than 61,000 members of the Polish elite and intelligentsia leaders who were deemed unfriendly to Germany.

[86] In his final observations for Pope Pius XII, Hlond wrote: "Hitlerism aims at the systematic and total destruction of the Catholic Church in the... territories of Poland which have been incorporated into the Reich...".

The entirety of the Protestant clergy of the Cieszyn region of Silesia were arrested and deported to concentration camps at Mauthausen, Buchenwald, Dachau and Oranienburg.

The Polish language was forbidden to be taught even in elementary schools; landmarks from streets to cities were renamed en masse (Łódź became Litzmannstadt, and so on).

", or Nur für Deutsche ("Only for Germans"), commonly found on many public utilities and places such as trams, parks, cafes, cinemas, theaters, and others.

[89] An estimated total of 50,000 children, majority taken from orphanages and foster homes in the annexed lands, but some separated from their parents, were taken into a special Germanization program.

Göring, having stripped almost all of occupied Poland of its artworks within six months of Germany's invasion, ultimately grew a collection valued at over 50 million Reichsmarks.

The uprising, receiving little assistance from the nearby Soviet forces, eventually failed, significantly reducing the Home Army's power and position.

When this is added to the three million Polish Jews who were killed as a matter of policy by the Germans, Poland lost about 22% of its population, the highest proportion of any European country in World War II.

[114] When AK Home Army Intelligence discovered the true fate of transports leaving the Jewish Ghetto, the council to Aid Jews (Zegota) was established in late 1942, in cooperation with church groups.

[118][119] Aside from being sent to Nazi concentration camps, most ethnic Poles died through shelling and bombing campaigns, mass executions, forced starvation, revenge murder, ill health, and slave labour.

[122] British historian Simon Sebag Montefiore states that Soviet terror in the occupied eastern Polish lands was as cruel and tragic as the Nazis' in the west.

[citation needed] The Soviets then lobbied the Western Allies to recognize the pro-Soviet Polish puppet government of Wanda Wasilewska in Moscow.

[134] By this arrangement, often described as a fourth partition of Poland,[132] the Soviet Union secured almost all Polish territory east of the line of the rivers Pisa, Narew, Western Bug and San.

[18] On 21 December 1939, the Polish currency was withdrawn from circulation without any exchange to the newly introduced rouble, which meant that the entire population of the area lost all of their life savings overnight.

Among the arrested were Władysław Broniewski, Aleksander Wat, Tadeusz Peiper, Leopold Lewin, Anatol Stern, Teodor Parnicki, Marian Czuchnowski and many others.

[163] The wave of arrests led to forced resettlement of large categories of people (kulaks, Polish civil servants, forest workers, university professors or osadniks, for instance) to the Gulag labour camps and exile settlements in remote areas of the Soviet Union.