The expulsion and ghettoization of the Jews was decided when the arriving Wehrmacht troops preparing for the Operation Barbarossa, the invasion of the Soviet Union, needed housing close to the new German–Soviet frontier.
Selected members of the prewar political parties such as the Jewish Bund in Poland were imprisoned in the Lublin Castle and continued to carry out their underground activities from there.
[7] One widely feared collaborator was Szama (Shlomo) Grajer, owner of a Jewish restaurant and a brothel serving Nazis on Kowalska Street.
Most of the victims, about 30,000, were deported to the Belzec extermination camp (some of them through the Piaski ghetto) between 17 March and 11 April 1942 by the Reserve Police Battalion 101 from Orpo helped by Schutzpolizei.
[11] At the time of the liquidation of the ghetto, the German propaganda minister, Joseph Goebbels wrote in his diary, "The procedure is pretty barbaric, and not to be described here more definitely.
[12] However, others, including head of the Warsaw's Judenrat, Adam Czerniaków, at the time dismissed these reports of mass murders as "exaggerations".