The Einsatzgruppen

The Einsatzgruppen were basically Nazi death squads, who -- affiliated with local militia-- went around killing massive numbers of people in regions that the German military had conquered. They apparently killed 1-1.5 million Jews, over the course of a large number of operations, all well-documented in their field reports. Even if they exaggerated a little bit how many they killed, there is no doubt they killed huge numbers of innocent people-- thousands of men, women and children, especially Jews-- and committed horrible, horrible crimes, major war crimes. They also stole property from their victims.

The Einsatzgruppen committed the horrendous Babi Yar massacre, where 33,771 Jews from Kiev, Russia were slaughtered (note the 33 and the 77). Jews weren't the only victims, as at least 100,000 other people were killed there-- Soviet POWs, communists, Gypsies, Ukrainian nationalists and civilian hostages.

It's extremely hard to imagine this level of killing, no doubt. It's mind-boggling. So much death like this took place during WWII. Almost all of the killing was done by guns, typically for the mass murders, with the victims lined up next to a ditch. Again, why there was so little resistance is hard to imagine, even if they were tricked to get to the killing ditch. Nonetheless, it is clear this happened to some degree.

One odd passage from wiki on the Einsatzgruppen is this:
Upon entering Kaunas, Lithuania on June 25, 1941, the Einsatzgruppen released all of the criminals from the local jail and encouraged them to join the pogrom that were underway.[30] Between June 23–27, 1941, 4,000 Jews were killed on the streets of Kaunas by local people, and saw the first massacres of Jews in open pits committed by Lithuanian anti-Semites.[31] Particularly active in the Kaunas pogrom was the so-called "Death Dealer of Kaunas", a young man who murdered Jews with a crow bar at the Lietukis Garage before a large crowd that cheered each killing with much applause; he occasionally stopped to play the Lithuanian national anthem "Tautiška giesmė" with his accordion before resuming the killings[31][32] One German soldier described the scene:

A young man—he must have been a Lithuanian ... with rolled up sleeves was armed with an iron crowbar. He dragged out one man at a time from the group and struck him with the crowbar with one or more blows on the back of his head. Within three-quarters of an hour he had beaten to death the entire group of forty to fifty people in this way. I had a series of photographs of the victims ...

After the entire group had been beaten to death, the young man put the crowbar to one side, fetched an accordion and went and stood on the mountain of corpses and played the Lithuanian national anthem. I recognized the tune and was informed by bystanders that this was the national anthem. The behaviour of the civilians present (women and children) was unbelievable. After each man had been killed, they began to clap and when the national anthem started up they joined the singing and clapping. In the front row there were women with small children in their arms who stayed there right until the end of the whole proceedings.

I found out from some people who knew German what was happening here. They explained to me that the parents of the young man who had killed the other people had been taken from their beds two days earlier and immediately shot, because they were suspected of being nationalists, and this was the young man's revenge.[33]
So apparently, if this really happened, everybody was just a raving psychopath at this time in the war, just randomly killing people. And this was just some dude in Lithuania upset because his parents were killed. But it doesn't even make sense-- what GROUP is he getting victims from? And even assuming they just stood there until he dragged them to be bludgeoned to death, why? What did they have to do with his parents???? It's quite bizarre.

It is curious how the Nazis seem to have equated Jews with Communist Russians, and so used this as an excuse to kill them. Then there is this intriguing bit:
Himmler's appointment book shows that he met with Hitler on 18 December 1941, and in response to Himmer's question "What to do with the Jews of Russia?", Hitler is recorded as responding, "als Partisanen auszurotten" ("exterminate them as partisans").[88] Israeli historian Yehuda Bauer has commented that the remark is probably as close as historians will ever get to a definitive order from Hitler for the genocide carried out during the Holocaust.[88] Bauer added that is unclear whether Himmler's question meant that until that point it had not been decided to exterminate the entire Jewish population, or whether such a decision had already been taken and Himmler's question referred merely to the precise means of extermination.[88] At the time of their meeting, death camps were being constructed under Operation Reinhard, Auschwitz was being converted from a concentration camp to a death camp and Chelmno had already opened earlier that month.[88] Thus, Bauer contends that Himmler's question to Hitler could be about whether to deport Soviet Jews to the death camps or continue the existing policy of genocide under the guise of anti-partisan operations.[88]
Finally, again according to wiki:
After a time, it was found that the killing methods used by the Einsatzgruppen were inefficient: they were costly, demoralizing for the troops, and sometimes did not kill the victims quickly enough.[47] During a visit to Russia in August 1941, Himmler witnessed the Einsatzgruppen killings first-hand and concluded that shooting Jews was too much of a "psychological burden" for his men.[47] Out of "care and concern" for the Einsatzgruppen, Himmler felt there was a need for a "humane" way of killing—for the killers, that is, not the victims. Himmler ordered the development of gas vans,[47] and these were used by the Einsatzgruppen for mass killings from 1942.[98]
Still, such measures were thought not to go far enough. At the Wannsee Conference on 20 January 1942, Reinhard Heydrich and various leading state officials discussed a more sweeping plan for killing Jews in Europe. This ultimately led to the establishment of Vernichtungslagern or extermination camps containing gas-chambers. Under this and other plans, an estimated six million Jews and five million non-Jews would ultimately lose their lives.[99]
So if the Einsatzgruppen killed 1 million Jews, and then in the extermination camps 6 million more were killed, that gives 7 million total?