The question of how much Germans (and other Europeans) knew about the Holocaust while it was ongoing continues to be debated by historians. With regard to Nazi Germany, some historians argue that it was an open secret amongst the population, whilst others highlight a possibility that the German population were genuinely unaware of the Final Solution. Peter Longerich argues that the Holocaust was an "open secret" by early 1943, but some authors place it even earlier. However, after the war, many Germans claimed that they were ignorant of the crimes perpetrated by the Nazi regime, a claim associated with the stereotypical phrase "Davon haben wir nichts gewusst" ("We knew nothing about that").
With regard to German-occupied Europe, historians highlight that governments were acutely aware of the implications of their complicity, and that the general population, to varying degrees, were usually not aware of the implications of ghettoization and deportation. Governments such as the Vichy government in France have been posited to be acutely aware of their complicity with the Nazis' genocidal policies. With regard to general populations, the overall consensus amongst historians appears to be that many were aware of a hatred towards the Jewry, but not insofar that a significant comprehension of the Nazis' genocidal policies was reached.
Nazi Germany
Knowledge of the Holocaust in Nazi Germany is a recurrent historical issue. The precise number of people who knew of the Final Solution is unknown. The larger population were at least acutely aware of the Nazi Party's anti-Semitism, if not advocates of the movement themselves. Numerous perspectives emerge when examining the degrees to which the larger population were aware that anti-Semitic practices enabled by the Nazi Party would eventuate to ethnic cleansing of the Jewish population. However, many historians argue that Germans were provided information explicit enough to indicate that the Jewish people were being massacred.
Although the mass murder of Jews took place outside of Germany, the mass killing of Soviet prisoners of war occurred within it and at an early date. By mid 1942 an estimated 227,000 had died after being deported to Germany. Many Germans were aware of these killings. Some Germans tried to help the prisoners, by giving them food or even aiding escapees. According to the Security Service reports, many Germans called for the death of these prisoners out of fear that feeding them would reduce their own rations.
Availability of genocidal policies to the German public
Nazi policies were widely available to the population. Numerous speeches spoken by Hitler in 1942 allude to the destruction of Jews. Notably, on 24 February 1942, Hitler's speech celebrating the Nazi Party's foundation alludes to his prophecy of 30 January 1939 in which he foresaw the destruction of European Jews. This speech was then reported the following day in the Niedersaechsische Tageszeitung. Hitler publicly referenced his original 1939 prophecy at least four times in public in the year 1942. Historians such as Confino and Koonz argue that Hitler's emphasis on this prophecy during the height of the holocaust meant that it became a shared ideal among the society.
From the analysis of primary sources circulating during the Second World War, historian Ian Kershaw deduces that areas of Germany closer to Poland and Russia had more knowledge of the ongoing extermination of Jews, as they were physically closer to the killing areas. The names of extermination camps are rarely mentioned in primary sources originating from the Western side of the Reich. Comparatively, areas near the east of Europe make references to the camps. Particularly, primary sources report the Polish resistance movement comparing the Katyn massacre to Auschwitz concentration camp.
Understanding the implications of deportation
Kershaw argues that there is a strong likelihood that German people understood the implications of deportation for evacuated Jews. There were numerous reports of mass shootings conducted in the Soviet Union, and it was known to the general German Public that this was where German Jews would be deported to. Similarly, Kershaw argues that local SD reports provided enough information such that Germans who wanted to seek the purpose of deportation would likely find the answer. In July 1942, Karl Duerckefaelden, a Celle engineer, noted three instances in his everyday life where rumours of deportation circulated. A conversation with a Dutch lorry driver, news from the BBC, and the wife of a Jew all spoke of the deportation of Jews and the potential implications of death.