National and University library (NUK) was established by a decree, released by the Empress Maria Theresa in 1774. Around 637 books, spared by a fire, were henceforth available for public use in the newly established library of the Ljubljana Lyceum.
After World War I, in 1919, it was renamed the State Reference Library, thus becoming the central library of Slovenia.
With the foundation of the first Slovenian university in Ljubljana, the library served also as the central university library.
Plans for the new University Library were created between 1930 and 1931 by the architect Jože Plečnik. However, claims for a new Slovenian university library encountered resistance by the authorities, which were then based in Belgrade. Persistent student protests and demonstrations nevertheless brought an end to it. As a result, in 1941 the University Library moved into a new monumental building in the immediate vicinity of the University. Plečnik’s Library is an exquisite cultural monument.
After liberation in 1945, the University Library was legally recognised as the Slovenian national library and it was again renamed the National and University Library.