The National Library of Israel holds more than 200 personal archives and collections of German-Jewish intellectuals from the 19th and 20th century. In 2021/2022, a joint project with the University of Hamburg catalogued and digitized 24 of the most important holdings. This article surveys the complex characteristics of the material and points to its significance for scholarship through three exemplary dimensions: personal entanglements, multilingualism, and migration histories. It also addresses the challenges of accessing and managing more than 700,000 digital images and shows the potentials they hold for future research. The article serves as an introduction to this special issue.