The discovery of a hair in one of Nicolaus Copernicus’s books helped to identify the astronomer’s remains. This event received such widespread media coverage that it is unlikely anyone will ever again think that Uppsala University Library is inadequate.

Gustav II Adolf carried out a series of reforms in Sweden, covering various areas of the country’s functioning – from the military to education. Within the latter, Uppsala University played a key role; in the king’s view, it was to serve as a Lutheran stronghold of knowledge, standing in opposition to Catholic initiatives. The main ‘competition’ in Sweden came from the Jesuit colleges, which, although based on the continent, were geared towards operating in Sweden, amongst other places. The king was particularly averse to them, as they allowed young people, amongst other things, to make use of their library collections; moreover, they also provided free accommodation. The Jesuits in Braniewo, Warmia, also carried out this sort of activity. They continued to run the school founded by the Bishop of Warmia and Grand Secretary of the Crown, Stanisław Hozjusz (1504–1579), whose aim was to restore Catholicism in Sweden and Prussia (Colegium Hosianum).

A change in the university’s operations was necessary here, if only because, in its early years, the institution did not enjoy a good reputation amongst either professors or prospective students. The king donated property to the university and also secured its funding. Furthermore, he established scholarships for students and ordered the appointment of foreign lecturers. All these measures were aimed at improving the quality of education and, consequently, enhancing Uppsala’s reputation as an academic city.

The university library played a key role in this new vision for the institution; although the university was founded in 1477, – was not established until the 1620s. It was founded in accordance with the concept of a large universal library, which was in keeping with the specialised book collections previously made available at the faculties of European universities. Along with the charter establishing the library, the king bequeathed to the university authorities a collection of books, most of which came from the Vasa collection, but some of which had been brought to Sweden as spoils of war, for example from Riga (1622), Frombork and Braniewo (1626) or Würzburg (1636).

The royal donation comprised almost 4,500 volumes of various origins. As a result, the university needed space to store them safely, and so work began on refurbishing the premises of the future library. To ensure professional management, a qualified librarian was employed, and rules governing the use of the collection were drawn up. Over time, confidence in the library grew amongst noble families; for example, Magnus Gabriel De la Gardie donated a collection of manuscripts, as he believed that the storage conditions there would be better than at home. As it later transpired, this was not always the case; the situation only changed after the collections were moved to the Gustavianum (1691), i.e. the building which now houses the university museum.

Among the holdings donated to the university library is a unique collection of so-called ‘Copernican works’. This is a collection of books that belonged to or were used by Nicolaus Copernicus. Following the death of the astronomer (1543), who held the position of canon at Frombork Cathedral, these books were transferred to the libraries of the Frombork chapter and the Jesuit college in Braniewo, and subsequently – during the Polish–Swedish War of 1626–1629 – looted and taken away by the Swedes. They initially ended up at the Royal Castle of the Three Crowns (Tre Kronor) in Stockholm, where they were catalogued by the librarian and antiquarian Johannes Bureus, and subsequently transferred to the University Library in Uppsala.

The books were identified at the turn of the 19th and 20th centuries, and it was decided at that time to separate them from the general collection, creating the Copernican Collection, which currently comprises 46 volumes. Detailed research into the books is currently underway, as doubts have arisen in historiography as to whether all the books actually belonged to the astronomer. Furthermore, there were uncertainties regarding where Copernicus was buried, and so a search for his burial site began in 2004. After the skull of a man aged around 70 was found, measurements were taken and, following computerised reconstructions, it appeared that these matched the astronomer’s portraits. To be certain, Copernicus’s book collection was searched for additional DNA traces, namely hair. Ten hairs were found in the book *Calendarium Romanum magnum* from 1518. (the book was identified by comparing, amongst other things, Copernicus’s handwriting with that in surviving letters and marginal notes in the book) and a comparison of the genetic material was carried out. As a result, two hairs were found to have the same genetic code as the skull.