Translated from German, "Erntefest" means "Harvest Festival." "Erntefest" was the code name for the German action which aimed to murder all remaining Jews in the Lublin District of the General Government (Generalgouvernement, or German-occupied Poland) in the fall of 1943.

Nazi officials initiated Operation "Harvest Festival" in response to several insurgencies conducted by surviving Jews in the German-occupied East. In the spring and summer of 1943, German occupiers encountered armed resistance in the ghettos of Warsaw and Bialystok. On August 2, 1943, Jewish prisoners rebelled at the Treblinka killing center, while an insurgency at the Sobibor killing center on October 14, 1943, facilitated the escape of over 300 prisoners; 58 of these survived the war. The Aktion Reinhard killing centers were liquidated in the autumn of 1943, in the wake of prisoner uprisings at Sobibor and Treblinka. Fearing further insurrections in the General Government, SS chief Heinrich Himmler ordered the murder of the remaining 45,000 Jewish prisoners engaged in forced labor in the Lublin district. Most of these were deployed as forced laborers at the Trawniki, Poniatowa, and Majdanek camps.

"Erntefest" began at dawn on November 3, 1943. SS and police units surrounded the Trawniki and Poniatowa labor camps. Jews were then removed from the camps in groups and shot in nearby pits dug for this purpose. At Majdanek, Nazi officials first separated Jews from the other prisoners. They were then marched to nearby trenches and shot. Jews from other labor camps in the Lublin area were also transferred to Majdanek for shooting. Music played through loudspeakers at both Majdanek and Trawniki camps to drown out the noise of the mass shootings and to mask the screams of the victims. At Majdanek and Trawniki, the killing operation was completed in a single day. At Poniatowa the shootings concluded on November 4, lasting two days.

Approximately 42,000 Jews were killed during "Erntefest," the largest German-perpetrated massacre of the Holocaust.