Szmalcownik

Szmalcownik (Polish pronunciation: [ʂmalˈtsɔvɲik]); in English, also sometimes spelled shmaltsovnik) is a pejorative Polish slang expression that originated during the Holocaust in Poland in World War II and refers to a person who blackmailed Jews who were in hiding, or who blackmailed Poles who aided Jews, during the German occupation. By stripping Jews of their financial resources, blackmailers added substantially to the danger that Jews and their rescuers faced and increased their chances of being caught and killed.

In the capital of Poland, Warsaw, some 3,000–4,000 people acted as blackmailers and informants. In the summer of 1942, Żegota, a Polish underground organization dedicated to aiding the Jews, requested that the Polish Underground State intensify its efforts to stop the "blackmailer plague". In the summer of 1943, the Home Army began carrying out death sentences for szmalcowniks in occupied Poland, executing more than a dozen by the end of the war. The number and effect of these executions is disputed. A number of szmalcowniks were also tried in Poland after the war.

The phenomenon of blackmailing Jews during the Holocaust was not unique to Poland, and occurred throughout occupied Europe.