The authorwss depicts the history of a dispersed musical collection, which was held at the libraries of Könisgsberg before the Second World War. The research, aiming to find and identify the fragments of lost collections, realized at the Polish RISM Centre at the National Library in Warsaw, enabled the authoress to locate several copies from the Königsberg collection in libraries in Poland (Warsaw and Torun), Germany (Göttingen and Berlin) and Lithuania (Vilnius). Three items included in the catalogue of the Department of Rare Books at the Kalingradskii (since 2005 Rossiiskii) Gosudarstvennyi Universitet im. Immanuela Kanta, not present in the RISM catalogues, are the main objects of investigation. They contain three musical treatises by Johannes Eccard and Nikolaus Zangius as well as partbooks of several occasional compositions, described in the article.