Currently, the Ossoliński National Institute comprises of the Ossolineum Library, the Museum of the Lubomirski Princes, the Pan Tadeusz Museum and the Ossolineum Publishing House. The Ossolineum collections feature around 2,000,000 units and include books, periodicals, manuscripts, documents, old prints, drawings, engravings, paintings, bookplates, medals, coins, seals, maps and plans, posters, brochures, placards and microform collections. All collections are accessible on site in eight reading rooms and are also sometimes presented during exhibitions organised by the museums and the library. The Ossolineum Publishing House, the oldest continuously operating publishing house in Poland, publishes contemporary essays and prose, classics, scientific and popular literature, as well as materials on the history and current activities of the Ossoliński National Institute.

Since its early days, the Institute has also published its own scientific periodical, whose title has changed several times over the years – currently it is the annual “Czasopismo Zakładu Narodowego im. Ossolińskich”.

The Ossoliński National Institute was established in 1817 on the initiative of Count Józef Maksymilian Ossoliński pursuant to a decision of Emperor Francis I. The basis of the Ossolineum collection was the founder’s Viennese collection, transported after his death (1827) to Lviv. Over the years, the collections of the Institute have grown successively. Before the outbreak of the Second World War, the Ossolineum had one of the largest collections of historical memorabilia and library collections in Poland in the scope of humanities, especially history, literature and related fields, while the Ossolineum Publishing House was one of the leading outlets publishing scientific works, school textbooks, as well as a series of critical studies of texts of Polish and foreign literature, i.e. the “National Library”.

During the war, the Institute’s library collection grew, as many people donated their own collections to the Ossolineum in order to save them from destruction. This is how the Institute received perhaps the most famous object of its entire collection – the manuscript of Adam Mickiewicz’s Pan Tadeusz, deposited by the Tarnowski family from Dzików. The Ossolineum Library was managed by successive occupation authorities (Soviet and German). The Museum of the Lubomirski Princes was liquidated and its collections were distributed among emerging Ukrainian institutions.

After the end of the war and geopolitical changes, part of the Ossolineum’s Lviv collection (approximately 30% of the former collection, mainly library collections) was transported to Wrocław. The Ossoliński National Institute – at the time it was the Library and the Publishing House – was incorporated into the Polish Academy of Sciences in 1953 and for many years the two institutions functioned independently of each other. The collection of the Museum of the Lubomirski Princes remained almost entirely in Lviv.

In 1995, the Parliament of the Republic of Poland passed a law transforming the Institute into a Foundation. Thanks to this change, it became possible to reinstate the Museum of the Lubomirski Princes and reincorporate the Publishing House into the structure of the Ossoliński National Institute.

In subsequent years, the Ossolineum began cooperation with the Vasyl Stefanyk National Academic Library in Lviv, which holds a significant part of the Institute’s historical collection. An agreement between the two parties enabled the copying of collections, conservation work was carried out jointly, and several catalogues of library and museum collections were also produced on the basis of the Lviv archives. The cooperation dedicated to library and museum collections was interrupted by the outbreak of war in Ukraine.