The Library of Antonio Maria Graziani. Books and Papal Diplomacy between Italy and Poland in the Late 16th Century

The relationship between books and early modern diplomats has recently emerged as a central focus of historical research. This interest reflects broader transformations in the study of diplomacy, now understood not merely as a matter of international relations, but as being deeply embedded in the social and cultural systems of early modern Europe. Against this backdrop, the book collection of Antonio Maria Graziani (1537-1611) offers a particularly illuminating case study. His private library, reconstructed through the Nuncio’s Secret Archives (NSA) project, not only reflects his rich and multifaceted intellectual biography, but also serves as a privileged source for understanding his work in papal diplomacy. In particular, the collection sheds light on how a diplomatic agent of the Roman Church could mobilize his books to intervene in the complex religious landscape of multiconfessional Europe. Building on this perspective, this essay examines Graziani’s library as a “space of diplomatic strategy”, with a focus on Poland, where he operated at the highest levels for over two decades. The analysis develops along three main lines. First, it shows how Graziani’s books help reconstruct previously underexplored diplomatic networks of political and confessional solidarity between the upper echelons of Polish Catholicism and the Roman Curia. Second, it examines how Graziani’s “Polish bookshelf” granted him access to valuable sources of information that supported his diplomatic efforts in the region. Third, it investigates specific reading practices documented in Graziani’s books, which played a key role in his work as papal envoy.