The Project

About Yahad

Our Mission

Yahad Encyclopedia is the digital reference platform of Yahad-In Unum, a Paris-based organization dedicated to the field investigation and documentation of Nazi and Soviet mass crimes. Founded by Father Patrick Desbois, Yahad-In Unum has conducted over 22 years of systematic research across Ukraine, Belarus, Poland, Russia, Romania, and other countries formerly under Nazi occupation.

This encyclopedia is the culmination of that work — a structured, evolving archive that brings together more than 1,400 eyewitness testimonies, thousands of archival documents, geolocated killing sites, and the scholarship of historians, forensic researchers, and field investigators from around the world.

Our mission is twofold: to preserve the memory of victims who were murdered and buried in unmarked mass graves, and to make the evidence of these crimes accessible to researchers, educators, students, and the general public in a form that is both scholarly and humane.The encyclopedia is designed to serve as a living reference — continuously updated as new findings emerge from archives, as previously unknown killing sites are identified through witness testimony and forensic work, and as the scholarly understanding of the Holocaust continues to evolve.

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Editorial Policy

Sources and Verification

All encyclopedic articles published on this platform are based on primary sources — archival documents, witness testimonies, forensic reports, and field investigation records — cross-referenced against peer-reviewed secondary literature. Every factual claim is footnoted and linked to its source where digitally available.Testimonies are presented in their original languages with verified translations. Witness identities are partially anonymized (initial surname) unless explicit written consent for full identification has been given.

Scholarly Review

Articles undergo a two-stage editorial review: internal review by Yahad-In Unum researchers, followed by external peer review by at least one independent historian specializing in the relevant period or geography. Disputed interpretations are clearly flagged within the text.The encyclopedia does not publish opinion or advocacy. Its remit is documentation, historical analysis, and the preservation of evidence.

Corrections and Updates

All articles carry a publication date and a last-reviewed date. Significant corrections are logged in a visible corrections note appended to the article. When new archival findings substantially change an established understanding, the article is revised and the change is noted.

Language and Terminology

We follow the terminology established by the International Holocaust Remembrance Alliance (IHRA). Place names are given in their current official form, with historical names noted in parentheses on first use. Perpetrator rank and unit designations are given in German, with English translations.

Editorial Board: The Yahad Encyclopedia Editorial Board comprises historians, archivists, and field researchers affiliated with Yahad-In Unum, the Paris Institute of Political Studies, the Hebrew University of Jerusalem, and the United States Holocaust Memorial Museum. Board membership is reviewed annually.

Contact

For research inquiries, editorial questions, corrections, partnership proposals, or media requests, please use the contact details below. We aim to respond within five working days.

Address

Yahad-In Unum

20 rue Joseph Bouvard

75007 Paris, France

General enquiries

contact@yahadinunum.org

Research & Archives

archives@yahadinunum.org

Phone

+33 (0)1 45 67 89 00

Main website

www.yahadinunum.org