Roger Moorhouse, a historian who has published a number of books on the Second World War, is set to speak at Hitchin Library later this month.
In a talk entitled 'The Holocaust by Bullets: the story of the Einsatzgruppen killings', Moorhouse will be speaking about an "often missing chapter" of the Holocaust.
The Einsatzgruppen death squads took part in killing Jewish people and others across Nazi-occupied Europe, often by shooting them.
Some historians estimate that they murdered more than two million people, including 1.3 million Jewish people.
During the talk, Moorhouse will speak about who they were and how they operated at the event. Among his books on Nazi Germany are Killing Hitler and Berlin at War: Life and Death in Hitler's Capital, 1939-45.
His most recent book is First to Fight: The Polish War 1939, about the September Campaign that opened the Second World War in Europe. The Einsatzgruppen took part in the German invasion of Poland during the campaign.
The event is being held on Thursday, January 26, at 6.30pm and tickets are available online or from the library itself. They cost £7, or £5 for concessions.
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