In the autumn of 1941, the Nazis started preparing for a major project: the murder of more than two million Jews who lived in the occupied part of Poland. The order was issued by Heinrich Himmler, head of the SS. After an attack on SS man Reinhard Heydrich in June 1942, the project was named after him: Aktion Reinhard.
The Nazis built three extermination camps to carry out their project. These camps were located in areas that were hard to reach: Belzec, Sobibor, and Treblinka. The Majdanek work camp already existed but was expanded with gas chambers. The camps were completed in the spring of 1942. The Jews from the ghettos were put on transport to the camps and murdered in the gas chambers upon their arrival.
By the end of 1942, almost 1.3 million Polish Jews had been murdered. In November 1943, Aktion Reinhard was terminated. The camps were emptied, and the bodies of the victims were excavated and burned. Then the Nazis planted trees on the grounds to wipe out all traces of their crimes. All Jewish prisoners from camp Majdanek were murdered.
In total, this project resulted in the murder of more than two million Jews. The Polish Jews were not the only ones who were murdered in the camps: victims also included Jews from France, Yugoslavia, the Soviet Union, the Czech Republic, Slovakia, Austria, and the Balkans. In Sobibor, over 34,000 Dutch Jews were murdered in 1943.