This dissertation reconstructs the private library of the Polish nobleman Władysław Konstanty Wituski (1603–1655) from its surviving remains by cataloging the printed books from his collection preserved at Skokloster Castle and his handwritten school notebooks housed in the Swedish National Archives in Stockholm. Wituski’s book collection was taken from Poland as war booty during the Swedish-Polish war of 1655–1660. Its preservation is particularly remarkable in the light of the fate of other early modern libraries of the nobility in the Polish-Lithuanian Commonwealth, which were largely dispersed or destroyed as a result of a succession of wars over the centuries.

Through bibliographical analysis, the study explores Wituski’s book ownership and reading habits, emphasizing his engagement with specific works through handwritten marginalia and flyleaf notes. The bindings in Wituski’s collection offer valuable insights into the material culture of early modern libraries of the nobility in the Commonwealth. By comparing his library to other book collections of the Polish-Lithuanian nobility and to a contemporary treatise on the ideal noble library by Jakub Kazimierz Haur, the study evaluates the degree to which Wituski’s collection conformed to the book-owning practices of his social milieu, and identifies notable divergences.

Drawing on Wituski’s notebooks and correspondence, the study also examines his education at the Jesuit College in Pułtusk and at the Kraków Academy, his educational journey through Denmark, the Dutch Republic, and England, and his service in the Dutch West India Company in Brazil. Additionally, the study investigates Wituski’s parliamentary career, his duties associated with the so-called land offices which he held, and his ties to the Vasa court.

This dissertation demonstrates how Wituski’s library is intertwined with both his personal biography and the broader socio-political, intellectual, and religious currents of his time. A close examination of his collection has uncovered previously unknown aspects of Wituski’s life while also reaffirming established facts. The books he owned reflect the breadth of his experiences – ranging from his formal education, travels, and courtly connections to his political involvement and land management. This case study of his library also provides insight not only into the book-owning practices, but also the world of ideas, cultural needs, and aspirations of the Polish-Lithuanian nobility in the seventeenth century, which in turn further enhances our understanding of their private libraries.