Holocaust deniers question selected fragments of accounts or documents. In their view, finding isolated mistakes or inaccuracies in such texts disqualifies them outright as a historical source.

This stance stems from a lack of elementary knowledge about the work of historians, who always have to verify their sources by confronting them with other sources and ultimately assessing them critically in accordance with the principles of their scholarly craft. Therefore, it is not the case that a historian takes all the information from an analysed document for granted. On the contrary, before commencing their work, historians must ask themselves some basic questions: who the author was, whether they were willing and/or able to disclose the truth, and what limitations could have made the account incomplete or even completely erroneous. This critique concerns both narrative materials—primarily Survivors’ accounts and testimonies—and SS-documented orders, reports, statistics or the minutes of meetings. Generally, information is considered credible only if it fits within the logical sequence of events, a specific cause-and-effect chain and, above all, can be independently confirmed by other historical sources.

In the case of KL Auschwitz, a surprisingly large number of such sources have survived, despite the SS’s attempts to destroy and burn all documentation before the final evacuation in January 1945. Moreover, the crimes committed in this camp were also testified by witnesses, who were far more numerous than the survivors of Treblinka, Sobibor or Belzec. As a result, the history of Auschwitz is among the best documented of the German Nazi concentration and extermination camps.

Facts:

The primary sources of knowledge about the history of the Auschwitz camp are the accounts and testimonies of witnesses. These are found in the following archives:

• Auschwitz-Birkenau State Museum,
• Institute of National Remembrance,
• Jewish Historical Institute in Warsaw,
• US Holocaust Museum in Washington,
• Yad Vashem Institute in Jerusalem,
• Central Office of the State Justice Administrations for the Investigation of National Socialist Crimes in Ludwigsburg,
• Centre de Documentation Juive Contemporaine – Mémorial de la Shoah in Paris,
• Instituut voor Oorlogs-, Holocaust- en Genocide studies in Amsterdam,

as well as many other places.

Even assuming that some accounts were submitted by the same individuals not once, but two or three times, the total number of witnesses certainly reaches tens of thousands.

Survivors – former prisoners of Auschwitz,

• SS members of the camp staff,
• residents of Oświęcim and surrounding villages (including members of the resistance movement),
• civilian workers employed in the expansion of the camp and working alongside the prisoners on construction sites and in factories, chiefly in Upper Silesia.

The accounts were recorded in written form or preserved as audio or video recordings. Some of them are preserved in lawcourts in the form of testimonies (submitted under the penalty of perjury)—these include, in particular, large sets of case files from postwar trials in Poland against members of the Auschwitz camp SS staff as well as the so-called Auschwitz trials in Frankfurt am Main in the 1960s.

Many other accounts were submitted to the Auschwitz State Museum after the war; these were sometimes supplemented with handwritten corrections by the authors or the comments of historians and archivists.

Remaining accounts include the memoirs written by former prisoners on their own initiative and later donated to the Museum Archive or other institutions. Many of these were also published as books.

Among the thousands of such memoirs, accounts and testimonies, one will inevitably find various inaccuracies and errors—particularly in the chronology of events or specific numbers—which is a natural phenomenon.

In none of these sources (with the obvious exception of the court interrogations of most of the SS defendants) do the witnesses—former prisoners—deny the existence of gas chambers at Auschwitz or the mass murder that occurred there. The only former prisoners who had no information about the Holocaust were those who had been transferred, released or escaped before the mass exterminations using Zyklon B began in the spring of 1942.

A section of the Museum’s main exhibition displaying the accounts, testimonies and memoirs of Survivors, written in various countries during a period of over eighty years since the end of the war. Source: A-BSM.

Among the testimonies written during the war, the following in particular should be mentioned:

• the manuscripts of Sonderkommando prisoners, which they had hidden (buried) near the Birkenau crematoria,
• the secret messages and reports written by resistance movement members and smuggled out of the camp,
• correspondence illegally smuggled out of the camp to avoid SS censorship,
• the reports of those who had escaped from the camp—both Poles and Jews.

In addition to the narrative sources, another foundation of knowledge about the mass murders committed at Auschwitz are the German documents found after the war in the Auschwitz camp, other Nazi institutions and other concentration camps to which Auschwitz prisoners had been transferred.

Of the key sets of records, the most important in confirming the existence and functioning of the gas chambers in Auschwitz include:

• transport lists (Transportlisten) of Jews sent to Auschwitz from transit camps in various countries of Europe, sometimes containing last-minute deletions of individuals withdrawn from the transport and the inclusion of the names of those added to make up the transport quota;
• collective lists of Jews from various transports who were given prisoner numbers (Zugangslisten Juden – nicht fotografiert);
• similar lists of registered prisoners, including Jews as well as other deportees, prepared by members of the resistance movement (Liste der Männertransporte, corresponding lists for women, and separate lists of male and female Jews assigned numbers preceded by the letters A and B).

The above sources indicate that from the commencement of regular selections of Jewish transports on the Auschwitz ramps, the number of deportees began to dramatically exceed, by several orders of magnitude, the number of prisoners registered in the camp.

Moreover, there exist:

• a few surviving reports on the results of selections on the Birkenau ramp after the arrival of transports, prepared by the KL Auschwitz Employment Department;
• statistical summaries compiled at Bletchley Park based on SS radiograms intercepted and deciphered by British cryptologists during the war;
• extensive files of the Central Construction Office of the SS and Police Auschwitz O/S containing information about the planning and progress of construction work, including the construction of crematoria and gas chambers;
• files of the Camp Administration Department (Verwaltung), including certificates for purchase and delivery of Zyklon B;
• files of the camp Employment Department (Arbeitseinsatz), including reports of the number of prisoners employed in the Sonderkommando;
• photographs of the burning of corpses in incineration pits, taken by members of the resistance movement within the Sonderkommando;
• photographs taken by the SS, showing the selection procedure on the Birkenau railway ramp, from the arrival of a transport of Jews to the place where the deportees waited to enter the gas chambers;
• SS photographs showing the progress of work on the construction of the crematoria and gas chambers;
• aerial photographs of Auschwitz and Birkenau taken by the pilots of Allied reconnaissance aeroplanes in 1944, showing the plumes of smoke rising from the incineration pyres;

as well as many other documents containing information confirming the existence of gas chambers.

Construction work on crematorium No. IV. Seen here are the chimneys, the walls of the undressing room and the gas chamber. December 1942. Source: APMA-B.

Above all, the Museum grounds contain the ruins of the crematoria and gas chambers, which, despite having been blown up by the SS, still retain their clear functional layout. Moreover, Gas Chamber and Crematorium I building have survived in the Auschwitz I main camp.

The ruins of Gas Chamber and Crematorium II. Source: PMA-B.