Evidence and documentation for the Holocaust

The Holocaust—the murder of about six million Jews by Nazi Germany from 1941 to 1945—is the most-documented genocide in history. Although there is no single document which lists the names of all Jewish victims of Nazi persecution, there is conclusive evidence that about six million Jews were murdered. There is also conclusive evidence that Jews were gassed at Auschwitz-Birkenau, the Operation Reinhard extermination camps, and in gas vans, and that there was a systematic plan by the Nazi leadership to murder them.

Evidence for the Holocaust comes in four main varieties:

• Contemporary documents, including a wide variety of "letters, memos, blueprints, orders, bills, speeches"; Holocaust train schedules and statistical summaries generated by the SS; and photographs, including official photographs, clandestine photographs by survivors, aerial photographs, and film footage of the liberation of the camps. More than 3,000 tons of records were collected for the Nuremberg trials.
• Later testimony from tens of thousands of eyewitnesses, including survivors such as Sonderkommandos, who directly witnessed the extermination process; perpetrators such as Nazi leaders, SS guards, and Nazi concentration camp commandants; and local townspeople. Moreover, virtually none of the perpetrators put on trial denied the reality of the systematic murder, with the most common excuse (where one was given) being that they were just following orders.
• Material evidence in the form of concentration and extermination camps, which still exist with various amounts of the original structure preserved, and thousands of mass graves containing the corpses of Holocaust victims.
• Circumstantial evidence: during World War II, the population of Jews in German-occupied Europe was reduced by about six million. About 2.7 million Jews were deported to Auschwitz-Birkenau, Kulmhof extermination camp, and the Operation Reinhard camps never to be seen or heard from again.

The perpetrators attempted to avoid creating explicit evidence and they also tried to destroy the documentary and material evidence of their crimes before the German defeat. Nevertheless, much of the evidence was preserved and collected by Allied investigators during and after the war, and the overwhelming evidence of the crimes ultimately made such erasure attempts futile. Collectively, the evidence refutes the arguments of Holocaust deniers that the Holocaust did not occur as described in historical scholarship.