The Bibliotheca Rosenthalia began as the personal collection of Leeser Rosenthal – an independent collector who assembled an impressive library including thousands of printed books alongside numerous manuscripts and rare items. After Leeser Rosenthal’s death his son George, who had settled in Amsterdam, donated his father’s collection to the City of Amsterdam where the library was given a home as part of the University of Amsterdam. The Bibliotheca Rosenthalia was an important site for Jewish scholarship – and the collection steadily grew over the years. When the Nazis invaded the Netherlands in 1940, the majority of the country’s Jewish population were deported to concentration camps, with their possessions seized. As the Bibliotheca Rosenthalia was held by the Dutch state it was not immediately confiscated – though the library’s reading room was closed shortly after the Nazis invaded. During the period in which the reading room was sealed some of the staff members of the Bibliotheca Rosenthalia worked to secret away some of the rare books and manuscripts which were hidden from the Nazis. It was not until 1944 that the Bibliotheca Rosenthalia was taken away in over 150 crates – the books were to become part of the Nazis’ Library for the Investigation of the Jewish Question. After the Nazis were defeated most of the library was recovered – much of it in the crates in which it had been taken away – and returned to the University of Amsterdam. Today the Bibliotheca Rosenthalia remains an important collection and is amongst the largest collections of Judaic books in Europe.
This book stamp is from a book looted by the Nazis and sorted by Colonel Seymour Pomrenze, one of “the Monuments Men,” at the Offenbach Archival Depot.
There are two scrapbooks of archival markings from the books sorted at the Offenbach Depot in the Seymour Pomrenze Collection held by the American Jewish Historical Society (Call number P-933) There is a finding aid for the collection here The digitized scrapbooks are available here and here.

For more information on this project check the Center’s blog: 16thstreet.tumblr.com/tagged/Offenbach-Depot

Dr. Mitch Fraas, Acting Director of the Digital Humanities Forum at the University of Pennsylvania Libraries' Special Collections Center is working on a similar project for the German book stamps based on NARA microfilm of the volumes the American Jewish Historical Society currently holds. See viewshare.org/views/mfraas/offenbach-bookplates/

The Center for Jewish History would like to acknowledge the following: The American Jewish Historical Society, who graciously allowed the use of their archival materials and digital content; Mitch Fraas, Acting Director of the Digital Humanities Forum at the University of Pennsylvania Libraries' Special Collections Center, for his data and technical assistance in this project; David Rosenberg, Reference Services Research Coordinator, and Melanie Meyers, Senior Reference Services Librarian for Special Collections, for managing and creating the digital map; and Reference Services Intern Ilya Slavutskiy for his work on translating and mapping.