The Sonderkommando were Jews who were forced to work in the death camps found at Auschwitz-Birkenau, Sobibor, Treblinka, Majdanek and Belzec. The Sonderkommando were made to do tasks that can only repulse - yet they had no choice. By simply being in the Sonderkommado, they were doomed to death.
The death camps set up in Poland were extermination factories the like of which the world had never seen. The Wannsee Conference had made it plain just what the Nazis wanted to do with the Jews of Europe - introduce a programme of mass extermination. The Jews would be murdered, along with other racial/religious groups, on a scale that beggared belief. However, the SS guards in the various death camps simply could not have coped with the sheer volume of work. They therefore used Jews sent to the camp. They were known as the Sonderkommando - 'Special Commandos'.
The jobs of the Sonderkommado were simple - to clear out the gas chambers once those inside had been murdered. They then had to dispose of the bodies - usually supervised by just a handful of SS guards or guards from the Ukraine who worked for the SS. The Sonderkommando had to remove gold teeth from the victims, work in the crematoriums, burn the bodies - basically anything the SS told them to do.
Who 'became' a Sonderkommando? Young males who appeared to be in good health were the obvious choice. For those at the death camps, the choice was simple - immediate death in the gas chambers or work for the SS. However, belonging to the Sonderkommando only prolonged the inevitable. The SS were determined to ensure that there were no witnesses to the crimes committed at the death camps - so the men in the Sonderkommando were sure to die one way or another. If they refused to do what the SS required them to do, they were shot on the spot or sent straight to the gas chambers.
At most of the death camps, the Sonderkommando lived 'better' lives than those forced to do work of a more basic nature and they were kept strictly away from other prisoners still alive in the camps. The Sonderkommando usually got more food and could frequently wear their own clothing. However, they were always living on borrowed time.
At Auschwitz-Birkenau, there was a rebellion by the Sonderkommando who knew that they would also be killed eventually. In October 1944, the men in Birkenau Three Sonderkommando rose up against their SS guards. They were joined by Birkenau One Sonderkommando. The revolt ended in failure and all involved were executed.
After the war ended in 1945, those Sonderkommando who managed to somehow survive the death camps were treated with little compassion. They were treated as collaborators and some were executed for their work within the camps. However, the one defence given to them was that they had a simple choice - the gas chambers or working as a Sonderkommando, though that also meant eventual death.