The work examines the medieval library of the former Premonstratensian imperial abbey of Weissenau near Ravensburg. An updated catalog of the manuscripts, which are now widely scattered (from Princeton to St. Petersburg), has been created. The book presents the codices produced in Weissenau and thereby provides a picture of the scriptorium, its scribes, and painters. By including the benefactors of the monastery as well as the external and content-related features of Weissenau manuscripts, it reflects the history and unique characteristics of the library. For the first time, the codices in St. Petersburg were examined. Numerous previously unpublished illustrations, especially from St. Petersburg and Prague, complement the text.