In September 1941, German forces invading the Soviet Union took the city of Kyiv, in what is now the nation of Ukraine, and soon afterward perpetrated one of the most horrific acts of genocide in history. On September 29, they forced much of Kyiv’s Jewish population to go to Babi Yar, also known as Babyn Yar, a ravine located just outside the city.

After being ordered to undress, the victims were forced into the ravine, where they were shot by the SS and German police units and their auxiliaries. As the SS later reported to headquarters in Berlin, 33,771 Jews were executed over two days, according to the U.S. Holocaust Memorial Museum.

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The Babi Yar massacre was the apex of “Holocaust by bullets,” a term used by historians to describe the shooting executions perpetrated by the Nazis during World War II, which continued even after they began killing European Jews on a massive scale with poison gas in death camps such as the Auschwitz complex in Poland.

“What makes Kyiv’s Babyn Yar stand out within the Holocaust as a whole is that a metropolitan city in Europe lost virtually all of its remaining Jewish inhabitants to premeditated murder, for the first time in history, and more Jews died in it than in any other single German massacre,” explains Karel Berkhoff, an historian and co-director of the European Holocaust Research Infrastructure.

“Babyn Yar is also the most widely known instance of a specific type of killing in the Holocaust: mass murder near the places where the victims were living, usually by shooting them.”

A wave of shooting executions by Germans had started in the summer of 1941, in places such as Lithuania and Latvia as anti semitism escalated to violence, according to Edward B. Westermann, a professor of history at Texas A&M University-San Antonio and author of the 2021 book Drunk on Genocide: Alcohol and Mass Murder in Nazi Germany.

As German forces created an occupation zone, Hitler’s Nazi regime was able to carve out Lebensraum, or “living space,” to accommodate future German colonists, and at the same time eliminate a huge portion of the Jewish population of eastern Europe, according to Berkoff.

By the time Germans reached Kyiv in mid-September 1941, about 100,000 of the city’s prewar Jewish population of 160,000 already had fled or joined the Soviet military to fight the invasion, according to the Holocaust Memorial Museum. That left 60,000 Jews who had been unwilling or unable to flee—many of them women, children, the elderly and people who were ill.

A few days after the Germans seized Kyiv, bombs that had been left behind by Soviet forces went off in several buildings that Germans were using, according to Berkhoff. About 200 of the occupiers lost their lives, and the Germans soon retaliated by arresting and executing several hundred people. But that wasn’t enough.

On September 26 the German Army and the SS concluded that Kyiv’s Jewish population wouldn’t be confined in a ghetto, but instead annihilated at Babi Yar, a site that the Germans already had used to execute and bury Soviet officials. Two days later, on September 28, police posted 2,000 copies of a notice around the city and suburbs, ordering all Jewish residents to appear the next morning at an intersection in the city’s Lukianivka district, with all their personal documents, money and valuables and warm clothing.

The thousands who showed up that morning may have expected that they were going to be sent to labor camps. Instead, they were organized into groups by the Germans, and ordered to walk to Babi Yar.

“The fact that the victims were ordered to assemble and report to German authorities, and the fact that they had to march through the largest city in Ukraine on their way to the killing site, demonstrated the true extent of Nazi goals involving the destruction of the European Jews,” Westermann says.

When the Jews got to Babi Yar, the Germans seized their identification papers and burned them, making it obvious that no one would leave alive. Most of the victims were then chased through a gauntlet of Germans armed with rubber clubs and sticks, who beat them as they made their way to the ravine. They were ordered to undress and then lined up and shot with machine-gun fire standing up, or lying down. Infants were taken from their parents’ arms and thrown into the ravine.

The slaughter lasted the first day until about 5 or 6 p.m., but the Germans weren’t able to kill everyone. Those who remained were imprisoned in garages that night, until the executioners resumed their work the next day, according to Berkhoff. Bulldozers then covered the bodies with layers of soil.

It wasn’t until nearly two months later that word of the massacre was published by the Jewish Telegraph Agency Daily Bulletin, which reported that the victims “were systematically and methodically put to death.”

The gunfire at Babi Yar wasn’t over, though. “The ravine was used over the course of the German occupation as a killing site until 1943 for both Jews and non-Jews with an estimate of 100,000 victims,” Westermann says. All in all, as many as two million people were shot to death in mass shootings by Nazi forces.

After the war, the memory of the terrible events at Babi Yar didn’t go away. But attempts to commemorate Kyiv’s Jewish victims were suppressed by Joseph Stalin’s regime. When the Soviet government finally greenlighted a monument to be erected in the 1970s, they dedicated the site to “Kyiv residents and prisoners of war,” and didn’t mention Jewish identity.

Eventually, in independent Ukraine, a commission was established in 2016 to plan a full-scale memorial center. That site, still under construction, narrowly escaped damage from a Russian missile strike against a TV tower in Kyiv in March 2022.