The ZPP was a mass organization with about 100,000 members ( Polish citizens in the Soviet Union , mostly war refugees and Soviet deportees left after the departure of Anders ' Army ) . It was dominated by former members of the Communist Party of Poland , in particular people from the Central Bureau Communists of Poland , which was established after the ZPP and also operated in the Soviet Union . The ZPP included activists of many political orientations . In January 1943 , Wanda Wasilewska and Alfred Lampe petitioned the Soviet authorities for creation of an all-encompassing Polish center in the Soviet Union ; it would function as a " counterweight for the reactionary ( Polish ) émigré elements " . According to Wasilewska , the name of the organization was Stalin 's idea . The ZPP was organized from 1 March and its significance increased after the Soviet Union broke relations with the Polish government-in-exile in April 1943 , following the discovery of the Katyn massacre
Katyn massacre
Katyn massacre
Union of Polish Patriots