Skip to main content

Harry W. Mazal Holocaust collection

Identifier: COU:1806

Scope and Contents

The Harry W. Mazal Holocaust Collection consists of rare books and pamphlets related to the Holocaust, anti-Semitism, prejudice, and war crime trials, as well as some 500,000 documents, contemporary newspapers, microfilms, and photographs. The books, pamphlets, documents, and newspapers are in a wide variety of languages, including English, German, French, Polish, Hebrew, Yiddish, Ladino, Spanish, Italian, Dutch, Russian, Ukrainian, Lithuanian, Estonian, Latvian, Czech, Hungarian, Portuguese, and Flemish. The collection contains complete sets of the International Military Tribunal (IMT), the Nuremberg Military Tribunals (NMT), the Trial of Nazi Conspiracy and Aggression (NCA), and a complete set of the published British war crime trials. Other war crimes trials in Poland, USSR, Holland and other countries are also included, as well as the evidence presented at most of these trials. Notably, the collection contains a complete set of the several hundred-thousand documents presented in Nuremberg Trial Case No. 11: The "Ministries Case," United States against Ernst von Weizsaecker et al., together with a bound set of 130 volumes that originally belonged to the Deputy Chief Counsel Robert M. W. Kempner. The collection also holds a complete collection of contact negatives and aerial photographs taken by the Americans, the British, and the Germans of the concentration camps in Auschwitz (Auschwitz I, Birkenau, and Monowitz). The images were acquired from the National Archives and Records Administration in College Park, MD. This collection is also one of the largest repositories of Holocaust denial literature in the world, both because of Mazal’s passion for documenting Holocaust deniers and because of U.S. law that allows such material to circulate. Mazal also collected a vast array of memorial books (yizker bikher) that show how postwar Jewish communities came together across the globe to commemorate their histories in the creation of books. Additionally, the collection documents the history of American antisemitism, especially domestic manifestations of Nazism in the form of its newspapers, literature, and other ephemera.


  • Creation: Majority of material found within 1920 - 2011

Conditions Governing Access

This collection is open for access. Research access to original moving image films in this collection is restricted, due to preservation concerns. Contact with a list of desired items and a statement of intended use, which will be evaluated by the Moving Image Archivist based on preservation condition of the desired items and staff availability; please note that access may not be guaranteed for all items. All analog sound recordings, video formats, and badly deteriorated film held by the Archives must be digitized for research access, due to preservation concerns. If these materials have not previously been digitized, the researcher is responsible for the cost of digitization. Researchers may request access to previously-digitized audiovisual materials that are not online on the CU Digital Library by contacting

Copyright Statement

Limited duplication of materials allowed for research purposes. The University Libraries do not own the copyright to this collection. Researchers are responsible for contacting the copyright holder(s) for this material and obtaining permission to publish or broadcast. The University Libraries will not grant permission to publish or broadcast this material and are not responsible for copyright violations resulting from such use.

Biographical Note - Harry W. Mazal

Harry W. Mazal was born in 1937 and raised in Mexico City, Mexico. Although his parents were Sephardic Orthodox Jews, Mazal was raised Protestant, only discovering that he was Jewish in his teenage years. Mazal believed that his parents chose to not raise their children Jewish in order to protect the family from antisemitism. Similar to other families during that period, his family did not speak about the Holocaust or the war. Mazal would learn later in his adult life that much of his grandmother’s family, who was from Salonika, Greece perished in the Nazi camps Auschwitz, Treblinka, and Stutthof.

In 1967, together with his wife Jerry, Mazal traveled to Germany, a trip that had a profound impact on his life. While in Germany, he began to learn more about World War II and the history of the Holocaust. A voracious reader, Mazal began to immerse himself in Jewish history, focusing on the impact of WWII.

In 1990, the Mazals moved to San Antonio, Texas. Around this time, Mazal became aware of the growing presence of groups denying the Holocaust, especially on the Internet. Given the Nazis’ habit of keeping meticulous records of their atrocities, Mazal found it difficult to believe that anyone could deny the Holocaust, so he dedicated himself to refuting and discrediting Holocaust denial by collecting historical documents. Mazal traveled the world to research and collect materials on the Holocaust, and by 1993, his collection had outgrown the shelves of his house. He built the first of three expansions to his home, which ultimately became the Mazal Holocaust History Library. Among his more notable acquisitions was the entire fifteen volume set of the Nuremburg War Crimes trials, documentation of the Eichmann trial, and an oversized book about the construction, plans, and operations of the gas chambers at Birkenau. Funded entirely with Mazal's own money, the library was open primarily to researchers and scholars from around the world.

Materials from the Harry W Mazal Holocaust Collection played an important role in the libel case filed in British courts by David Irving against noted Emory University Holocaust scholar and historian, Deborah Lipstadt.

Harry Mazal passed away in 2011.

The Mazal Holocaust Library - Vision and Mission

From the Vision and Mission Statement of the Mazal Holocaust Library by Aimee Mazal Skillin (2011)

"This book collection began operating as a research library in 1993 as a source for information that could be used to combat Holocaust deniers and anti-Semites on the various dial-in bulletin Boards that existed long before the Internet began to operate.

From the outset it was decided that the books, documents and other material would focus primarily on documenting the Holocaust, the events leading up to that sad period, and the postwar effects of the death of six million innocent souls.

Although the Bulletin Boards only reached a relatively small number of people, many individuals were offended by allegations that the Holocaust had never taken place or worse, that it did take place but that not enough Jews were killed. It was immediately apparent that denial and anti-Semitism could only be combated with facts backed by incontrovertible evidence. The few people who confronted hatred knew that that nothing that was said would ever convince deniers, whose agenda has less to do with truth than with an ingrained dislike of the Jews. The hope was then, and continues to be, that our writings would minimize the effects of what deniers say by drawing more people to the truth rather than to hatred.

It was apparent from the beginning that deniers and Jew-haters had a lot of money and access to vast amounts of information on the death camps, the Nazi regime, the gas chambers, the Ghettos, etc., that they used – by distorting or editing the original material – to further their cause. These bigots continue to be amply funded. Their intent at that time, as it is now, was to minimize the Holocaust and to exculpate Hitler and his odious Nazi regime.

The best sources for facts and evidence on the Holocaust are: books written by scholars, transcripts of war crime trials, documents issued by the perpetrators, eyewitness reports, photographs, etc. Most of this information was not available in San Antonio, sadly not even in the Holocaust Memorial. Our only viable solution was to acquire the material and organize it in such a way that it could be accessed rapidly by researchers. Hence the Mazal Holocaust Library was created. Years of acquisitions and a major investment have resulted in what is arguably the world’s largest private library on the Holocaust.

To make the material accessible it was necessary to classify the books – we use a version of the Dewey Decimal System – and to protect them from damage. All books are covered with Mylar covers and are displayed on shelves in a climate controlled environment.

Considerable space was required for the growing collection. Originally housed in a spare bedroom, the library, needed to expand. Three additions to the house were made with specially designed bookshelves. A space to house the computer servers was also incorporated.

From the beginning, students and researchers have asked for access to the material. As many of the books are written in every European language (and Hebrew!), and because much of the material being collected is fragile or extremely rare, we opted for not allowing the general public to use the library. Students referred to by their professors, and researchers on the subject are always welcome and indeed encouraged.

The collection presently consists of over 25,000 books and pamphlets related to the Holocaust, anti-Semitism, prejudice, and war crime trials. Also in the library are some 500,000 documents, contemporary newspapers, microfilms and photographs. The library is organized using a computer-based index card system employing the Dewey decimal system. Approximately half of the books have so far been classified and are in the stacks. Book purchases continue as new and old material is discovered.

The books, pamphlets, documents and newspapers are in a wide variety of languages: English, German, French, Polish, Hebrew, Yiddish, Ladino, Spanish, Italian, Dutch, Russian, Ukrainian, Lithuanian, Estonian, Latvian, Czech, Hungarian, Portuguese, and Flemish. Brief descriptions of the contents of most of the foreign language books have been provided by volunteers, some of them survivors of the Holocaust.

Housed in the library are complete sets of the: International Military Tribunal (IMT) consisting of 42 volumes; Nuernberg Military Tribunals (NMT) consisting of 15 massive volumes; Nazi Conspiracy and Aggression (NCA) consisting of 11 volumes; and a complete set of the published British war crime trials. Other war crime trials in Poland, USSR, Holland and other countries are also covered. The library has undertaken to scan and digitize the text from these trials and place it on the Internet. Eleven of the 15 volumes of NMT and four of the 42 volumes of the IMT are already on the web site.

The library also owns a complete collection of contact negatives and aerial photographs taken by the Americans, the British and the Germans of the concentration camps in Auschwitz (Auschwitz I, Birkenau, and Monowitz). The images were acquired from the National Archives and Records Administration in College Park, MD. These are not usually available in any public or university library. Scanned copies of some of the images are available on one of our web sites. Information obtained from one of the images was used as evidence in the libel trial brought by Holocaust denier David Irving against Prof. Deborah Lipstadt of Emory University.

A complete collection of NO- (Nuremberg Organization) documents used in the various Nuremberg Trials was given to our library by the United States Holocaust Memorial Museum. These documents were used as evidence of the crimes perpetrated by the Nazi organizations. Like the other Nuremberg collection (see below) these documents are in very poor condition. The library has been scanning these papers and placing them on one of the websites in order to preserve them for posterity.

A complete set of the several hundred-thousand documents presented in Nuremberg Trial Case No. 11: The "Ministries Case", United States against Ernst von Weizsaecker et al. together with a bound set of 130 volumes that originally belonged to the Deputy Chief Counsel Robert M. W. Kempner. This vast collection, also entrusted to us by the United States Holocaust Memorial Museum, is on very deteriorated paper and will be scanned and placed on our web site at some point in the near future when sufficient funding is available.

The Holocaust History Project - Vision and Mission

From the Vision and Mission Statement of the Mazal Holocaust Library by Aimee Mazal Skillin (2011)

"The Mazal Holocaust Library was created to combat Holocaust Denial but by the early 90’s the birth of the WWW made it necessary to develop new techniques and other strategies, thus the creation of the Holocaust History Project.

By 1994, a new phenomenon in communications became available to the general public. The World Wide Web overnight gave every person in the world with a computer and a connection to the Internet the ability to establish web sites and publish whatever information he/she wished. Websites were and continue to be free from censorship or almost any other restrictions.

The Internet was like a gift from heaven for Holocaust deniers and bigots. Dozens of new sites promoting denial and hatred were immediately created. Today these numbers are in the thousands. With no constraints, deniers were – and are – able to publish the most hateful and outrageous lies about what happened to the Jews during the Nazi regime.

To counter such an onslaught, the Holocaust History Project was formed by a group of men and women who had, until then, been combating denial and anti-Semitism on the bulletin boards. From its modest beginning on March 25, 1998, THHP (as we will refer to the Holocaust History Project) has become one of the most important sites in the world dedicated to exposing lies and, more important, to producing original and documented essays relevant to the Holocaust.

From the beginning the founding members of THHP decided that the study of history should not be limited to historians. A multi-disciplinary approach to history would strengthen knowledge and reduce the sort of errors in which Holocaust deniers take delight.

One simple example should suffice to show the importance of a multi-disciplinary approach:

In 1994, renown Holocaust denier Robert Faurisson visited the ruins of the gas chamber of Crematorium 2 in Auschwitz-Birkenau. The building had been dynamited by the SS one day before the Soviet troops arrived in the camp. Faurisson wanted to establish whether or not four holes had been made in the roof through which Zyklon B could be dropped. Looking at the rubble he was unable to recognize any of these holes - which is not surprising given the absolute fragmentation of the concrete roof. After a perfunctory glance he stated, “No holes, no Holocaust!” This outrageous statement became the rallying cry of deniers all over the world.

Historians, who are usually not well versed in the engineering sciences, were stymied. They had no evidence other than some eyewitness reports to counter Faurisson’s argument.

In 1998 a team of researchers from THHP visited Auschwitz-Birkenau in an attempt to find the truth about the holes in the roof of the gas chamber. Included in that group were a Professor of Mathematics at Haifa University, a specialist in computer modeling and reconstructions, and a chemist who was also experienced in the construction of concrete structures. With the assistance of other specialists and with permission from the Director of the Auschwitz State Museum, this group made a forensic analysis of the roof and was able, after two years of study, to identify three of the holes.

The result of this research project was that (1) it was published by a prestigious journal issued by Oxford University Press; (2) it was used as evidence in the libel case brought against Prof. Deborah Lipstadt by a renown Holocaust denier, David Irving; and (3) it has silenced Holocaust deniers who can no longer claim that there were no holes in the roof.

By inviting lawyers, doctors, biochemists, engineers, linguists, and other specialties into THHP, the organization is able to view history from various perspectives.

When Prof. Deborah Lipstadt was sued in London for libel by the infamous Holocaust denier David Irving, she turned to us for evidence that would hamper or destroy his information. We provided her with a draft of our paper entitled: The Ruins of the Gas Chambers: A Forensic Investigation of Crematoriums at Auschwitz I and Auschwitz-Birkenau. This document was, in her opinion, the key piece of evidence that demolished Irving’s case. Suffice it to say that Prof. Lipstadt is an active member of THHP as is another brilliant historian, Prof. Robert Jan van Pelt.

THHP is presently formed by some thirty-two persons in eight countries. Many of the members are not Jewish. Each member is a Director and is entitled to vote in all matters that affect the operation and content of the web site.

The thirty-two members of THHP are located in various countries in the world: Sweden (2), Germany (5). Denmark (2), Portugal (1), France (1), Canada (2), United States (21). The membership includes lawyers, engineers, businessmen, computer specialists, and historians (including Prof. Deborah Lipstadt, Prof. Robert Jan van Pelt, Prof. William Samelson, and Prof. John Zimmerman). Approximately half of the members are not Jewish, and two are Holocaust survivors.

From the time that THHP began keeping records on the Holocaust History web site it has received upwards of 433 million "hits" and 75 million "accesses." Viewers have downloaded hundreds of megabytes of information. Thousands of students and the public in general have asked questions about the Holocaust and each has received a documented response from one or more of our members. A Guest Book has registered hundreds of comments, mostly favorable.

The Holocaust History Project, Inc., was incorporated in November 1997, launching its web site, on March 25, 1998. On June 1, 1999, THHP became a not for profit corporation organized under the laws of the state of Texas, recognized by the U.S. government as a tax-exempt educational organization under Section 501(c)(3) of the Internal Revenue Code."


627 linear feet (140 LF of Archival Materials: 119 Containers (74 record boxes, 45 flat containers of various sizes), 5 drawers of microfilm, 10 flat file drawers. Approximately 490 LF of Cataloged Monographs )

Language of Materials



The Harry W. Mazal Holocaust Collection is the life work of Harry W. Mazal (1937 - 2011), a businessman from Mexico City, who made his home in San Antonio, Texas. With the help of numerous volunteers, Mazal dedicated his life, time, and financial resources to creating a vast repository committed to commemorating the victims of the Holocaust around the world. His goal was to promote scholarly research and human understanding grounded in Holocaust studies while also fighting Holocaust denial, anti-Semitism, and bigotry. As a result, Mazal became an internationally recognized Holocaust collector and researcher.

A significant U.S. collection outside of the Holocaust museums in New York and Washington D.C., the Harry W. Mazal Holocaust Collection is comprised of more than 20,000 books and 500,000 documents, pamphlets, photographs, and other materials, including original transcripts of the Nuremburg trials. It was acquired by the University of Colorado Boulder in January 2014.

Documenting the tragedy of European Jews before they, their relatives and descendants arrived in America, this collection anchors the Post-Holocaust American Judaism Collections and makes the University of Colorado Boulder one of the only places in the world to track the Jewish-American experience from the time of the Holocaust through the resurgence of American Judaism in the post World War II period to the vitality of Jewish-American life today.


When the collection was moved from San Antonio to Colorado, much of the original order was lost. When physically and intellectually organizing the materials in 2017 to create the findign aid, the processors used information from the original Mazal Library, Holocaust History Project, and notes from original inventories to recreate similar groupings where possible and applied archival best practices on the remainder of the materials. Analog and digital media (Series 8) have been kept intellectually separate, but note that they have subjects and categories that overlap across all other series.

Harry W. Mazal Holocaust Collection Series Arrangement

  1. Nazi War Crime Trials
  2. Administrative
  3. Research: History
  4. Research: Holocaust
  5. Research: Holocaust Denial, Revisionism, and White Supremacy
  6. Microfilm
  7. Maps
  8. Media (Analog and Digital)
  9. Cataloged Books - Available via CU Library Catalog
Harry W. Mazal Holocaust Collection
Jane Thaler and Samantha Mat; with assistance from Jacob Flaws, Jordan Klevdal, and Sydney Marshall. The collection was also partially inventoried/processed by Stephanie Yuhas, Gregg Drinkwater, Stephanie Klein, Joshua Siary, and many other students over the years. Many thanks also to the team of CU Boulder catalogers lead by Anna Ferris.
Description rules
Describing Archives: A Content Standard
Language of description
Script of description
Language of description note

Repository Details

Part of the University of Colorado Boulder Libraries, Rare and Distinctive Collections Repository

1720 Pleasant Street
184 UCB
Boulder Colorado 80503 United States