Imagine you are handed a single sheet of paper. On it, one number: 33,771. That is the count of human beings shot at Babi Yar, a ravine outside Kyiv, over two days in September 1941. Two days. Now hold that number against this: Babi Yar was not an exceptional event. It was one entry in a systematic ledger. We established in our first lecture that the SS was never a single, uniform entity. It was a bifurcated organization — Allgemeine-SS and Waffen-SS — held together by one ideological root. Today we examine the place where that root produced its most catastrophic fruit: the mobile killing operations in the East. The Einsatzgruppen were task forces of the Security Police and the SD — the SS intelligence service. The USHMM is precise on this point: they were not regular army combat units. They were SS and police personnel, organized to follow the advancing German military into newly seized territory. Their early tasks included identifying enemies of German rule, seizing important sites, and building intelligence networks. When Operation Barbarossa began in June 1941, the mission transformed. Mass murder expanded dramatically. The primary targets became Communist Party officials, Soviet state functionaries, Roma, and above all, Jews — of every age, every gender. Think of it as a policy shift documented in their own operational reports: from selective targeting to systematic annihilation of entire communities. The USHMM estimates the Einsatzgruppen organized and helped carry out the shooting of more than half a million people in the first nine months of the Eastern Front war alone. Total estimates range from at least 1.5 million to possibly more than 2 million victims. The method was mass shooting — at fields, forests, and ravines outside towns. In some cases, gas vans were used. Here is the critical structural point, James. The Einsatzgruppen did not operate in isolation. They worked alongside German military units and local collaborators. Some occupied populations — particularly in Ukraine, Latvia, and Lithuania — supplied auxiliary police who assisted with roundups and shootings. The killing apparatus was a cooperative system, not a rogue unit operating outside German authority. After the war, the Einsatzgruppen became the subject of Case Nine of the Subsequent Nuremberg Proceedings — formally, United States v. Otto Ohlendorf, et al. Twenty-four defendants were tried. The tribunal found twenty guilty on all three counts: crimes against humanity, war crimes, and membership in a criminal organization. Fourteen death sentences were imposed, though only four were ultimately carried out. Notably, the indictment accused the defendants of murdering between 723,661 and one million people as part of a systematic program of genocide — making this among the earliest major legal proceedings to use that term in a formal legal context. The Einsatzgruppen were not a sideshow. They were an integral instrument of Germany's occupation strategy in the East — staffed by SS and police personnel, supported by military structures and local auxiliaries, and documented in their own situation reports. The Holocaust in the East was not incidental to the war. It was built into the architecture of the campaign from the beginning. That is what the evidence shows. And here is the detail that should stop you cold, James. Those convicted defendants — men found guilty of organizing mass murder on a documented, industrial scale — were gradually released. Sentences were commuted, shortened. The last were freed in 1958. That is thirteen years after the war ended. Thirteen years. The gap between the documented crime and the sustained consequence is itself a historical fact worth examining. So let us close with the precise takeaway. The Einsatzgruppen were staffed by SS and police personnel. They operated as an integral part of Germany's occupation architecture, not outside it. They were documented in their own situation reports, corroborated by army rear-area correspondence, survivor testimony, and postwar trial evidence. The Holocaust in the East was not improvised. It was organized, reported upward, and built into the campaign from the beginning. The bifurcated SS — Allgemeine and Waffen — shared one ideological root. The Einsatzgruppen are where that root produced its most measurable, most documented, and most catastrophic consequence.