For genealogists of Jewish families, tracing the 6 million Jewish victims that disappeared without a trace has been a challenge. More than 50 million documents are held at the International Tracing Service (ITS) at Bad Arolsen, Germany. For years, this archive has collected documents to help trace what happened to family members.
For decades after World War II, the files were used only to help find missing persons or document atrocities to support compensation claims. But in November, the last of the 11 countries that govern the archive under the auspices of the International Committee of the Red Cross cleared the way for public access.
Since then, interest has skyrocketed. Erich Oetiker, deputy director of the archive, said while the staff of 400 continue to process some 1,000 tracing requests per day, there are now also near daily visits from historians or individuals eager to trace a lost person's fate or view an original document.
The archive has little information online, almost everything is on paper. Other major Holocaust collections exist at the U.S. Holocaust Memorial Museum in Washington D.C., as well as Israel's Yad Vashem—both of which hold digitized copies of part of the collection—along with the Polish Institute for National Remembrance.
You can find more information at:
International Tracing Service: http://www.its-arolsen.org
U.S. Holocaust Memorial Museum: http://www.ushmm.org
The Washington museum has drawn up a list of more than 150 German keywords with English translations to use in computer searches: http://itsrequest.ushmm.org/its/Glossary.pdf.