The Herzog August Bibliothek (HAB) is an independent research institute specializing in the study of European cultural history in the medieval and early modern period. The library’s holdings from these periods form an archive of Western culture that is nearly unique in its scope. Manuscripts, incunabula, early imprints and special collections such as graphic art and maps provide material for almost limitless investigation into European cultures of knowledge in a global context.

Since 2004 the library contributes to the field of digital emblem studies in close cooperation with the University of Illinois at Urbana-Champaign and the wider digital emblem studies community. A series of projects labeled "Emblematica Online" aims to digitize, index, and do research on two of the greatest collections of emblem books worldwide. The most important outcome of the project series' efforts is the Open Emblem Portal, a portal that provides access to more than 30000 emblems of six emblem book collections from the University of Illinois at Urbana-Champaign, the Herzog August Bibliothek Wolfenbüttel, Glasgow University, Utrecht University, Duke University, and the Getty Research Institute.