EN
This article presents the history of count Przezdziecki's Library from its beginnings in the 18th century to its almost complete devastation during World War II. Although it is only an outline, relatively multifarious primary and secondary sources were used (including archival materials from the Central Archives of Historical Records in Warsaw, the Archives of the Polish Academy of Sciences in Warsaw, and the State Archive of the Capital City of Warsaw). The initial part pertains to efforts of subsequent family members to create, deposit, make available for visitors, and finance the Library collection. In the second part three main categories of Library resources are described, namely archival manuscripts, printed books, and others (works of art, archaeological finds, maps and atlases). The wartime fate of the institution (1939-1945) is presented separately. Moreover, wartime loses and present localizations of small remains from this formerly excellent collection are enumerated. The paper is appended with four attachments: 1) a simplified genealogical table of the Przezdziecki family, 2) the Library map, 3) a list of lost works of art from the family collection, 4) a list of saved items deposited in the Jagiellonian Library in Krakow in 1945.