'deployment groups';[1] also 'task forces')[2] were Schutzstaffel (SS) paramilitary death squads of Nazi Germany that were responsible for mass murder, primarily by shooting, during World War II (1939–1945) in German-occupied Europe.

The Einsatzgruppen had an integral role in the implementation of the so-called "Final Solution to the Jewish question" (Die Endlösung der Judenfrage) in territories conquered by Nazi Germany, and were involved in the murder of much of the intelligentsia and cultural elite of Poland, including members of the Catholic priesthood.

As ordered by Nazi leader Adolf Hitler, the Wehrmacht cooperated with the Einsatzgruppen, providing logistical support for their operations, and participated in the mass murders.

[4] The Einsatzgruppen had their origins in the ad hoc Einsatzkommando formed by Heydrich to secure government buildings and documents following the Anschluss in Austria in March 1938.

[10][11] Heydrich placed SS-Obergruppenführer Werner Best in command, who assigned Hans-Joachim Tesmer [de] to choose personnel for the task forces and their subgroups, called Einsatzkommandos, from among educated people with military experience and a strong ideological commitment to Nazism.

[13] Heydrich instructed Wagner in meetings in late July that the Einsatzgruppen should undertake their operations in cooperation with the Ordnungspolizei (Order Police; Orpo) and military commanders in the area.

[10][20] The Einsatzgruppen performed these murders with the support of the Volksdeutscher Selbstschutz, a paramilitary group consisting of ethnic Germans living in Poland during Operation Tannenberg.

[26][27] Many senior army officers were only too glad to leave these genocidal actions to the task forces, as the murders violated the rules of warfare as set down in the Geneva Conventions.

[36] In May 1941, Heydrich verbally passed on the order to murder the Soviet Jews to the SiPo NCO School in Pretzsch, where the commanders of the reorganised Einsatzgruppen were being trained for Operation Barbarossa.

[37] In spring 1941, Heydrich and the First Quartermaster of the Wehrmacht Heer, General Eduard Wagner, successfully completed negotiations for co-operation between the Einsatzgruppen and the German Army to allow the implementation of the "special tasks".

[38] Following the Heydrich-Wagner agreement on 28 April 1941, Field Marshal Walther von Brauchitsch ordered that when Operation Barbarossa began, all German Army commanders were to immediately identify and register all Jews in occupied areas in the Soviet Union, and fully co-operate with the Einsatzgruppen.

[39] In further meetings held in June 1941 Himmler outlined to top SS leaders the regime's intention to reduce the population of the Soviet Union by 30 million people, not only through direct murder of those considered racially inferior, but by depriving the remainder of food and other necessities of life.

[4] Led by SD, Gestapo, and Kripo officers, Einsatzgruppen included recruits from the Orpo, Security Service and Waffen-SS, augmented by uniformed volunteers from the local auxiliary police force.

[49][50] The SS brigades, wrote historian Christopher Browning, were "only the thin cutting edge of German units that became involved in political and racial mass murder.

[71][72] However, SS-Brigadeführer Franz Walter Stahlecker, commander of Einsatzgruppe A, reported to his superiors in mid-October that the residents of Kaunas were not spontaneously starting pogroms, and secret assistance by the Germans was required.

Initially there was a semblance of legality given to the shootings, with trumped-up charges being read out (arson, sabotage, black marketeering, or refusal to work, for example) and victims being murdered by a firing squad.

[78] A situation report from Einsatzgruppe C in September 1941 noted that not all Jews were members of the Bolshevist apparatus, and suggested that the total elimination of Jewry would have a negative impact on the economy and the food supply.

[85] After being marched three kilometres (two miles) northwest of the city centre, the victims encountered a barbed wire barrier and numerous Ukrainian police and German troops.

[96] With the creation of units such as the Arājs Kommando in Latvia and the Rollkommando Hamann in Lithuania,[97] the attacks changed from the spontaneous mob violence of the pogroms to more systematic massacres.

[100] The 1940–1941 Soviet occupation had been profoundly traumatic for residents of the Baltic states and areas that had been part of Poland until 1939; the population was brutalised and terrorised, and the existing familiar structures of society were destroyed.

[126] Permanent killing centres at Auschwitz, Belzec, Chelmno, Majdanek, Sobibor, Treblinka, and other Nazi extermination camps replaced mobile death squads as the primary method of mass-murder.

[128] After the defeat at Stalingrad in February 1943, Himmler realised that Germany would likely lose the war, and ordered the formation of a special task force, Sonderaktion 1005, under SS-Standartenführer Paul Blobel.

[131] According to research by German historians Klaus-Michael Mallmann and Martin Cüppers [de], Einsatzkommando Egypt, led by Walter Rauff, was formed in 1942 in Athens.

Given its initially small staff of only 24 men, Mallmann and Cüppers point to the further history of the unit, when it was quickly enlarged to more than four times its original strength during its deployment in Tunisia.

[133] Former Iraqi prime minister Rashid Ali al-Gaylani and the Grand Mufti of Jerusalem Haj Amin al-Husseini played roles, engaging in antisemitic radio propaganda, preparing to recruit volunteers, and in raising an Arab-German Battalion that would also follow Einsatzkommando Egypt to the Middle East.

Now known as the Severity Order, it read in part: The most important objective of this campaign against the Jewish-Bolshevik system is the complete destruction of its sources of power and the extermination of the Asiatic influence in European civilization ...

[152] The German historian Peter Longerich thinks it probable that the Wehrmacht, along with the Organization of Ukrainian Nationalists (OUN), incited the Lviv pogroms, during which 8,500 to 9,000 Jews were murdered by the native population and Einsatzgruppe C in July 1941.

[154] British historian Hugh Trevor-Roper noted that although Himmler had forbidden photographs of the murders, it was common for both the men of the Einsatzgruppen and for bystanders to take pictures to send to their loved ones, which he felt suggested widespread approval of the massacres.

He states that those German generals who claimed that the Einsatzgruppen were a necessary anti-partisan response were lying, and maintained that the slaughter of about 2.2 million defenceless civilians for reasons of racist ideology cannot be justified.

[168] The responsible senior public prosecutor, Erwin Schüle [de], used as evidence documents from the American Einsatzgruppen trial in Nuremberg, existing specialist literature, SS personnel files, and surviving "USSR event reports".