The Warsaw Ghetto Uprising was the 1943 act of Jewish resistance in the Warsaw Ghetto in German-occupied Poland during World War II to oppose Nazi Germany's final effort to transport the remaining ghetto population to Majdanek and Treblinka concentration camps. After the Grossaktion Warsaw of summer 1942, in which more than a quarter of a million Jews were deported from the ghetto to Treblinka and murdered, the remaining Jews began to build bunkers and smuggle weapons and explosives into the ghetto. The left-wing Jewish Combat Organization and right-wing Jewish Military Union formed and began to train. A small resistance effort to another roundup in January 1943 was partially successful and spurred the Polish groups to support the Jews in earnest.
The uprising started on 19 April when the ghetto refused to surrender to the police commander SS-Brigadeführer Jürgen Stroop, who then ordered the burning of the ghetto, block by block, ending on 16 May. A total of 13,000 Jews died, about half of them burnt alive or suffocated. German casualties were probably less than 150, with Stroop reporting only 110 casualties [16 killed + 1 dead/93 wounded].