
Some three million non-Jewish Polish citizens perished during the course of the war, over two million of whom were ethnic Poles (the remainder being mostly Ukrainians and Belarusians). The vast majority of those killed were civilians, mostly killed by the actions of Nazi Germany. From the start, the war against Poland was intended as a fulfillment of the plan described by Adolf Hitler in his book Mein Kampf. The main objective of the plan was that all of Eastern Europe to become part of the greater Germany, and the Slavs were to be exterminated to make living space for the pure German race.
The intelligentsia was annihilated, the mentally ill patients were wiped out, and the rest were put into concentration camps and slave labor camps. Poles were prisoners in nearly every camp of the extensive concentration camp system in German-occupied Poland and the Reich. The Polish scholar Franciszek Piper, the chief historian of Auschwitz, estimates that 140,000 to 150,000 Poles were brought to that camp between 1940 and 1945, and that 70,000 to 75,000 died there as victims of executions, of human experimentation, and of starvation and disease. Between 1943 until 1944, the Konzentrationslager Warschau worked as a death camp to exterminate the Polish population of Warsaw. The Gentile population of Poland was a target of the łapanka policy, in which the forces of SS, Wehrmacht and police rounded up civilians on the street. Between 1942 and 1944, there were approximately 400 victims of łapanka in Warsaw daily.
The worse single event to wipe out the Poles happened during the Warsaw uprising atrocities. During the 1944 Warsaw Uprising, German forces committed many atrocities against Polish civilians, following the order by Hitler to annihilate the city and "turn it into a lake". The most severe of them took place in Wola district where, at the beginning of August 1944, tens of thousands of civilians (men, women, and children) were methodically rounded-up and executed by Einsatzkommando of Sicherheitspolizei operating within the SS-Gruppenführer Heinz Reinefarth group under overall Erich von dem Bach-Zalewski command.

