600 years of KU Leuven: from old to new

For centuries, scientists here have been searching with curiosity for answers to the small and large questions that occupy humanity. But from every answer springs a new question. One discovery thus follows another. Pushing the boundaries of science, inspiring students, and applying acquired knowledge for the world around us—that is what drives us. We keep searching, for knowledge knows no end. In 2025, KU Leuven turns 600, and this is being celebrated throughout the year, even with new exhibitions that continue into 2026!

Common affairs Leiden University and KU Leuven

In 2025, Leiden University and KU Leuven celebrate the 450th and 600th anniversaries. Many activities (lectures, exhibitions, walks, etc.) were organized. As Chair of the Executive Board, Luc Sels is responsible for the strategic direction and general administration of Leiden University. Within the Board, he is responsible for the portfolios of general coordination, strategy, valorization, international relations, communication and marketing, alliances, and external relations. Luc Sels is affiliated with the Faculty of Law as Professor of Strategic HRM and the Future of Work. From 2017 to 2025, Luc Sels was Rector of the KU LeuvenHe brings a rich academic background and extensive administrative experience. After obtaining his PhD in the social sciences (1995), he became a professor at the Leuven Faculty of Economics and Business in 2004, where he served as dean for nine years. Additionally, he was affiliated part-time with the universities of Bern and Rochester. In Flanders, he held various advisory and administrative positions, including at the High Council for Employment and as director of the Support Centre for Work. A woman appears in the logos of both universities.    

     

Timeline of university history

1425: The university is founded by Pope Martin V In 2025, KU Leuven celebrates its six hundredth anniversary. This places it, together with its sister university UC Louvain, among the oldest universities in Europe. It is also the oldest university in the Low Countries and worldwide among all still existing Catholic universities. The University of Leuven was formally founded by the bull issued by Pope Martin V on December 9, 1425. The city of Leuven had requested permission for the establishment with the support of Duke John IV of Brabant and the city clergy.

The 'Old University' – as we call the University of Leuven from its founding until 1797 – initially comprised four faculties: the Arts, Canon Law, Civil Law, and Medicine. In 1432, the Faculty of Theology was added with papal permission.

(From left to right and from top to bottom: City Hall, City Hall, KU Leuven University Library, University Hall, St. Peter's Church. Margin: historical city plan of Leuven from 1937 with an overlay of an atmospheric image of Marktrock on the Old Market. Stamp: Towers of the City Hall.) Upon its founding, the university was housed in what is today the University Hall is. The imposing building was put into use in 1317 as the city's cloth hall. Towards the end of the 17th century, the entire hall was ceded to the university. Since its university function, the venerable building has served as the administrative seat of the university, housing the offices of the rector and vice-rectors, as well as university services. For centuries, the University Hall also contained lecture halls and meeting rooms for the old faculties. In addition, the university court was located there. Together with the many tax exemptions enjoyed by the university community and the privilege to appoint its graduates to a number of ecclesiastical offices, all of this illustrates the great degree of autonomy that the university managed to retain into the 18th century. Incidentally, that independence was often a thorn in the side of secular and ecclesiastical authorities. [/ One_half] [one_half_last]             [/ One_half_last]   1516: The first edition of Utopia, Thomas More's socio-political satire, is printed in Leuven. Just over a century after its founding, the University of Leuven numbered some 2.000 students, including more than 200 foreigners. The influence of several great minds contributed to this, led by the humanist Desiderius Erasmus. He stayed in Leuven for several years and played an active role in the development of the still young university. His mediation for the printing and publication of the controversial work *Utopia* by is well known. Thomas More, which appeared in Leuven in 1516.

  1517: Erasmus founds the Collegium Trilingue (Latin, Greek, and Hebrew), a center of humanism. Furthermore, Erasmus the founder of the Collegium Trilingue, which was erected on the Leuven Fish Market in 1517. It was a center of humanist activity and can be considered the foundation of critical inquiry. With the contributions of thinkers and seekers from across Europe, Leuven henceforth continued to hold the pursuit of science in high regard, albeit with ups and downs, depending on the intellectual climate.

  1543: Andreas Vesalius publishes his handbook on anatomy: De humani corporis fabrica libri septem. 1569: One of the most important cartographers in history, Gerard Mercator, is the first to use the conformal map projection (Mercator projection). In the 16th century, Leuven was for a time a beacon for scholars from the entire continent. Great names such as the aforementioned Erasmus, the anatomist Vesalius, the cartographer MercatorThe mathematician Gemma Frisius, the educator Vives, and many others set the tone. In addition, the University of Leuven was a bastion in the struggle against the Reformation. Leuven maintained a relationship of loyalty towards the Church, without, however, being an ecclesiastical university. From its founding, it has stood as a “critical center of thought” in a healthy tension with the ecclesiastical authorities.

Over time, the university also increasingly shaped the cityscape. The numerous pedagogies (study houses for students) and colleges, often built with the support of generous donors, are scattered throughout the entire city center. Some can only be found thanks to a discreet commemorative plaque, while others have survived, albeit often with extensive renovations. The historical architectural image of the university in the city center is no longer medieval, but predominantly 18th-century.

  1723: Hendrik Jozef Rega creates the necessary infrastructure for modern scientific research: the Botanic Garden (1738), the Rega Wing for the library (1723), and the Theatrum Anatomicum (Anatomical Theatre) (1744). The intellectual heyday of the old university undoubtedly lay in the 16th century. In the centuries that followed, too, Leuven counted renowned scientists in its ranks. There was, for instance, the physician Jozef Rega, rector several times, who expanded the University Hall in 1738 with a wing that housed the library until the fire in 1914. Rega financed the Botanical Garden (1738), which was later transferred to the city, and the Anatomical Theatre (1744), the core of the city's medical campus. Physics research received its first impetus during the period of the Austrian Netherlands, with a 'cabinet' built in the old Arts Faculty building, the current Museum M. In the last quarter of the 18th century, Jan Pieter Minckelers experimented with coal gas as fuel for lighting. However, for thorough and structurally anchored scientific research, as at most universities, we had to wait almost another century.

  1797 – 1931: New impetus In the meantime, major political developments did not leave the University of Leuven unaffected. Sometimes it benefited from them, sometimes it passively endured the consequences. State interference was very significant in the 18th century. Its Catholic character did the university no good during the French occupation. In 1797, the university was dissolved. After a hiatus of nearly 20 years, King William I of the United Netherlands opened a state university intended to be neutral in 1817, which continued to exist until 1834. In that year, the Belgian bishops took the initiative to establish a Catholic university in Mechelen, which moved back to its familiar base in Leuven the following year.

Education at the 'returned home' university was initially primarily focused on a form of higher vocational training. Gradually, and certainly in the last quarter of the 19th century, university education came increasingly under the influence of rapidly developing scientific research. In the humanities, the Higher Institute of Philosophy was founded in 1889 with the aim of renewing critical thinking in contact with the success of the natural sciences. The young professor and later Cardinal Désiré-Joseph Mercier was the initiator. He understood that a modern university had to embrace the emerging natural scientific research. The university continued to strongly profile itself in the humanities, but increasingly developed the other scientific domains as well. It suffices here to refer to the groundbreaking research of the professor and priest. Georges Lemaitre, who contributed to general relativity and cosmology with his hypothesis of the expanding universe (1927), and can be considered the founder of the Big Bang theory (1931).   1954: KU Leuven in the Belgian Congo The Catholic University of Leuven established a university in the then Belgian colony of Congo under the name 'Lovanium'. After the independence of Congo in 1960, it was reorganized under the name 'Université Nationale du Zaïre' (UNAZA).

  1968: The bilingual university is divided into two institutions based on language: the Dutch-speaking KU Leuven and the French-speaking UCLouvain. The 'unitary' character of the University of Leuven, with French as the predominant language of communication, gradually grew into a thorny issue. The cautious transition to Dutch starting in 1911, when the first Dutch-language lectures were given, developed into a difficult political hurdle over the following half-century, and would eventually lead to what some called the 'third fire' of Leuven. The first two 'fires' had been caused by both world wars: the large, rich library went up in flames twice within a few decades. The 'third fire' soon proved not to be so disastrous at all. In the turbulent political context of the late 1960s, in which the unitary University of Brussels was also split up, the single University of Leuven was divided into two independent sister universities: on the one hand the 'Catholic University of Leuven' (KU Leuven), and the 'Université Catholique de Louvain' (UCL), on the completely new campuses of Louvain-la-Neuve (Ottignies) and Woluwé (Brussels). Both sister universities currently enjoy an excellent relationship with each other and have many partnerships in education, research, and organization.

1972: KU Leuven Research & Development (LRD) KU Leuven Research & Development (LRD) is established as one of the first technology transfer offices in Europe. LRD focuses on encouraging innovation and high-tech entrepreneurship and builds bridges between science and industry.   1985: Pope John Paul II visits the university. In his speech on this occasion, Rector Pieter De Somer emphasizes the importance of academic freedom.   Na 1968 Pieter De Somer became the first rector of the independent KU Leuven in 1968. The renewed university resolutely embraced an internationally oriented scientific development. Research grew rapidly, as did the number of students. Expansion was on the agenda, both in and around Leuven, with campuses for science and technology at the Arenberg Estate in Heverlee and for biomedical sciences at the Gasthuisberg site, where the new complex of the University Hospitals was built starting in the 1980s. A far-reaching development of a different nature, but also with major consequences for student and staff numbers, was the establishment of the KU Leuven Association in 2002. The association of KU Leuven with 14 Flemish universities of applied sciences was part of the harmonisation movement that set the entire European higher education system on new paths from 1999 (Bologna Declaration). Currently, the Leuven Association comprises five large clusters of universities of applied sciences. The academic programmes of these universities of applied sciences were fully integrated into KU Leuven in 2014. In 2014, there was an unprecedented reshuffling of the Flemish education landscape: the integration of academic higher education programs into the university literally brings university education closer to the student. In 2021, the Rega Institute developed a very powerful antiviral drug against dengue fever, according to the WHO one of the greatest threats to global health.

(Stamps: Historical image of the Sedes Sapientiae from the KU Leuven University Archives, surrounded by circles referring to the present. Sheet: Full image of the Sedes Sapientiae, with a text about the anniversary year 2025, marking the 600th anniversary of KU Leuven – UCLouvain.) [/ One_half] [one_half_last]             [/ One_half_last]   Future Today, KU Leuven has approximately 66.000 students, spread across various campuses in and outside Leuven. The university and the university hospitals employ a total of approximately 23.000 staff members. KU Leuven ranks among the top European research centers and can unequivocally consider itself a global player in a number of areas. At the same time, it remains proud of its rich history. “Based on its Christian view of humanity and the world, it aims to be a place of open discussion on societal, philosophical, and ethical themes, and a critical center of thought within and for the Catholic community,” according to its Mission Statement. KU Leuven never became the 'University of the Hageland,' as some feared after 1968, but has instead grown into a cosmopolitan institution in a rapidly renewing urban environment. The university has a prominent presence in the international scientific world. It retains its very own Christian humanist profile, in which hyper-advanced science goes hand in hand with livability and accessibility for talented individuals. For comparison: The city of Leuven has 104.812 inhabitants (as of January 1, 2025). With a papal bull of December 9, 1425, Pope Martin V founded the University of Leuven. Today, 600 years later, KU Leuven and UCLouvain are leading universities in the world. We look back on the rich history of this educational institution and look forward to the university of the future. Vatican City has issued a special stamp to commemorate the 600th anniversary of the University of Leuven. The stamp features an image of Pope Martin V, who recognized the university in 1425. At the initiative of Duke John IV of Brabant, with the papal bull “Divina Disponete”, Pope Martin V founded the University of Leuven in 1425, transforming the Belgian city into a center of culture and research of international importance. One of the university's most famous symbols is the statue of the Sedes Sapientiae, the “Seat of Wisdom”, an iconic representation of the Virgin Mary that has watched over students and the academic community for centuries. Located in the University Church of St. Peter, the Sedes Sapientiae embodies the connection between faith and knowledge, rooted in the university's educational mission. After six centuries, the Catholic University of Leuven continues to look ahead and remain true to its heritage of intellectual openness, research, and dialogue between different fields of knowledge. The stamp design was created by artist Patrizo Daniele. The artwork reproduces the two most representative elements of the university: the wooden statue of the Blessed Virgin Mary, known as “Sedes Sapientiae”, symbol and patroness of the university, and the likeness of Pope Martin V, who founded the university with the bull “Sapientie immarcescibilis” issued on December 9, 1425. Source: KU Leuven  

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600 years of KU Leuven with two exhibitions until February 22, 2026: https://www.kuleuven.be/600jaar/ Visit Leuven: https://www.visitleuven.be/ Previous 450 Years of Leiden University blogs: https://www.postzegelblog.nl/tag/450-jaar-universiteit-leiden/