Order Police battalions in the context of "Sonderaktion 1005"

Einsatzgruppen (German: [ˈaɪnzatsˌɡʁʊpm̩], lit. 'deployment groups'; also 'task forces') 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. Almost all of the people they murdered were civilians, beginning with the intelligentsia and swiftly progressing to Soviet political commissars, Jews, and Romani people, as well as actual or alleged partisans throughout Eastern Europe.

Under the direction of Reichsführer-SS Heinrich Himmler and the supervision of SS-Obergruppenführer Reinhard Heydrich, the Einsatzgruppen operated in territories occupied by the Wehrmacht (German armed forces) following the invasion of Poland in September 1939 and the invasion of the Soviet Union in June 1941. The Einsatzgruppen worked hand-in-hand with the Order Police battalions on the Eastern Front to carry out operations ranging from the murder of a few people to operations which lasted over two or more days, such as the massacre at Babi Yar (with 33,771 Jews murdered in two days), and the Rumbula massacre (with about 25,000 Jews murdered in two days of shooting). 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. Historian Raul Hilberg estimates that between 1941 and 1945 the Einsatzgruppen, related agencies, and foreign auxiliary personnel murdered more than two million people, including 1.3 million of the 5.5 to 6 million Jews murdered during the Holocaust.

The history of the Jews during World War II is almost synonymous with the persecution and murder of Jews which was committed on an unprecedented scale in Europe and European North Africa (pro-Nazi Vichy-North Africa and Italian Libya). The massive scale of the Holocaust which happened during World War II greatly affected the Jewish people and world public opinion, which only understood the dimensions of the Final Solution after the war. The genocide, known as HaShoah in Hebrew, aimed at the elimination of the Jewish people on the European continent. It was a broadly organized operation led by Nazi Germany, in which approximately six million Jews were murdered methodically and with horrifying cruelty. Although the Holocaust was organized by the highest levels of the Nazi German government, the vast majority of Jews murdered were not German, but were instead residents of countries invaded by the Nazis after 1938. Of the approximately 6 million Jews murdered by the Nazis, approximately 160,000 to 180,000 were German Jews. During the Holocaust in occupied Poland, more than one million Jews were murdered in gas chambers of the Auschwitz concentration camp alone. The murder of the Jews of Europe affected Jewish communities in Albania, Austria, Belarus, Belgium, Bosnia & Herzegovina, Channel Islands, Croatia, Czech Republic, Estonia, France, Germany, Greece, Hungary, Italy, Latvia, Libya, Lithuania, Luxembourg, Moldova, the Netherlands, North Macedonia, Norway, Poland, Romania, Russia, Serbia, Slovakia, and Ukraine.

Leading to World War II, nearly all Jewish businesses in Nazi Germany had either collapsed under financial pressure and declining profits, or had been forced to sell out to the Nazi German government as part of the "Aryanization" policy inaugurated in 1937. As the war started, massacres of Jews took place originally as part of Operation Tannenberg against the Polish nation. The much larger and methodical mass killings of Jews began with the onset of Operation Barbarossa in 1941. Led by Einsatzgruppen and the Order Police battalions, the destruction of European Jews took place with the active participation of local Auxiliary Police including Belarusian, Estonian, Latvian, Lithuanian, and Ukrainian units.

The Ordnungspolizei (Orpo, German: [ˈɔʁdnʊŋspoliˌtsaɪ], meaning 'Order Police') were the uniformed police force in Nazi Germany from 1936 to 1945. The Orpo was absorbed into the Nazi monopoly of power after regional police jurisdiction was removed in favour of the central Nazi government ("Reich-ification", Verreichlichung, of the police). In 1936, Heinrich Himmler, the commander (Reichsführer-SS) of the Schutzstaffel (SS), was appointed Chief of the German Police in the Interior Ministry. The top and upper leadership positions of the Orpo were filled by police officers who belonged to or had joined the SS. Owing to their green uniforms, Orpo members were also referred to as Grüne Polizei (Green Police). The force was established as a centralised organisation based in Berlin uniting the municipal, city, and rural uniformed police that had been previously organised on a state-by-state basis.

The Ordnungspolizei encompassed virtually all of Nazi Germany's law-enforcement and emergency response organisations, including fire brigades, coast guard, and civil defence. Himmler and Kurt Daluege, chief of the Orpo, worked to transform the police force into militarised formations ready to serve the regime's aims of conquest and racial annihilation. Police troops were first formed into battalion-sized formations for the invasion of Poland, where they were deployed for security and policing purposes, also taking part in executions and mass deportations. During World War II, the force was tasked with policing the civilian population of the occupied and colonised countries. In 1941, the Orpo's activities escalated to genocide after the Order Police battalions formed into independent regiments or were attached to Wehrmacht security divisions and Einsatzgruppen. Independently and in collaboration with those units, members of the Orpo perpetrated crimes against humanity and mass-murder during the Holocaust.

The Schutzmannschaft, or Auxiliary Police (lit. "protection team"; plural: Schutzmannschaften, abbreviated as Schuma) was the collaborationist auxiliary police of native policemen serving in those areas of the Soviet Union and the Baltic states occupied by Nazi Germany during World War II. Heinrich Himmler, head of the Schutzstaffel (SS), established the Schutzmannschaft on 25 July 1941, and subordinated it to the Order Police (Ordnungspolizei; Orpo). By the end of 1941, some 45,000 men served in Schutzmannschaft units, about half of them in the battalions. During 1942, Schutzmannschaften expanded to an estimated 300,000 men, with battalions accounting for about a third, or less than one half of the local force. Everywhere, local police far outnumbered the equivalent German personnel several times; in most places, the ratio of Germans to natives was about 1-to-10.

The auxiliary police battalions (Schutzmannschaft-Bataillone) were created to provide security in the occupied territories, in particular by combating the anti-Nazi resistance. Many of these battalions participated in the Holocaust and caused thousands of Jewish deaths. Usually the battalions were voluntary units and were not directly involved in combat. In total, about 200 battalions were formed. There were approximately 21 ethnic Estonian, 47 Latvian, 26 Lithuanian, 11 Belarusian, 8 Tatar, and 71 Ukrainian Schuma battalions. Each battalion had an authorized strength of about 500, but the actual size varied greatly. They should not be confused with native German Order Police battalions (SS-Polizei-Bataillone) which the Order Police formed between 1939 and 1945 and which also participated in the Holocaust.

Babi Yar (Russian: Бабий Яр) or Babyn Yar (Ukrainian: Бабин Яр) is a ravine in the Ukrainian capital Kyiv and a site of massacres carried out by Nazi Germany's forces during its campaign against the Soviet Union in World War II. The first and best documented of the massacres took place on 29–30 September 1941, in which some 33,771 Jews were murdered. Other victims of massacres at the site included Soviet prisoners of war, communists and Romanies. It is estimated that a total of between 100,000 and 150,000 people were murdered at Babi Yar during the German occupation.

The decision to murder all the Jews in Kiev was made by the German military governor Generalmajor Kurt Eberhard, the Police Commander for Army Group South, SS-Obergruppenführer Friedrich Jeckeln, and the Einsatzgruppe C Commander Otto Rasch. Sonderkommando 4a as the sub-unit of Einsatzgruppe C, along with the aid of the SD and Order Police battalions with the Ukrainian Auxiliary Police backed by the Wehrmacht, carried out the orders. Sonderkommando 4a and the 45th Battalion of the German Order Police conducted the shootings. Servicemen of the 303rd Battalion of the German Order Police at this time guarded the outer perimeter of the execution site.

Jürgen Stroop (born Josef Stroop, 26 September 1895 – 6 March 1952) was a German SS commander and perpetrator of the Holocaust during the Nazi era, who served as SS and Police Leader in occupied Poland and Greece from 1942-1943 (in Poland) and 1943-1944 (in Greece). He held the rank of SS-Gruppenführer und Generalleutnant der Polizei from 1942-1945 (equivalent to a Heer Generalleutnant/Lt-Gen in the Wehrmacht). He led the suppression of the Warsaw Ghetto Uprising in 1943 with German Troops consisted of Heer Troops including Waffen-SS and the Order Police battalions and wrote the Stroop Report, a twelve-page account of the operation annexed with many original documents and pictures. Following the defeat of Germany, Stroop was prosecuted during the Dachau Trials and convicted of murdering nine U.S. prisoners of war. After his extradition to Poland, Stroop was tried, convicted, and executed for crimes against humanity.