Does St Peter’s Church in Leuven really contain the remains of the Dukes of Brabant from the twelfth and thirteenth centuries? DNA research led by KU Leuven aims to provide a definitive answer over the coming years. The research project, which was recently launched, is a collaboration between the university, M Leuven and the Leuven aan de Dijle pastoral zone, with the support of the City of Leuven and the Province of Flemish Brabant.

The crypt of St Peter’s Church in Leuven contains human remains traditionally attributed to four Dukes of Brabant: Godfrey II, Godfrey III, Henry I and Henry II. These four men were key figures in the history of Brabant, particularly Henry I (c. 1165–1235), who ruled the duchy for more than 50 years and whose tomb can still be admired in St Peter’s Church.

“That earlier analysis of William II now offers us an exceptional opportunity to investigate the identities of the four Dukes of Brabant as well,” says Maarten Larmuseau, Professor of Genetic Genealogy and scientific coordinator of the project. “The remains, which were in a poor state of preservation, have since been removed from the crypt and professionally conserved. Ancient DNA analysis has recently begun, with the aim of examining, among other things, ancestry, kinship and biological characteristics.”

Sustainable preservation and public access

The project aims to make the region’s medieval past accessible and tangible to the wider public. Among other initiatives, digital facial reconstructions will be created to visually bring the dukes back to life. M Leuven is also exploring ways of sharing the story of the Dukes of Brabant more widely, both within St Peter’s Church itself and beyond.

Dukes of Brabant

“M Leuven considers it important to facilitate pioneering research and thereby increase our knowledge of the remains of the medieval dukes and improve their state of preservation. This forms part of a broader policy on research into medieval heritage at the museum,” says Marjan Debaene, Director of Old Masters at M Leuven.

“The Dukes of Brabant are illustrious forefathers from Leuven’s past who helped shape the early history of our city and our region. It is remarkable that this research allows us to come closer to them once again. Through the collaboration of strong Leuven-based partners, we are demonstrating our ambition to better understand and visualise our heritage and our past. Together, we are bringing a long-lost chapter back to life in a scientific and respectful way,” says Dirk Vansina, Leuven’s Alderman for Immovable Heritage.

“We are supporting this project in order to bring the story of the Dukes of Brabant and the origins of our region to life in a unique, scientifically grounded and accessible way. This partnership demonstrates how heritage, innovation and collaboration can go hand in hand in Flemish Brabant,” says Bart Nevens, Provincial Deputy responsible for heritage.

“It is a unique opportunity to gain insight into several successive generations of a medieval elite family. By the end of 2027, we hope to be able to provide more definitive answers about the identities of the dukes,” concludes Professor Larmuseau.

Picture: Tomb of Henry I

The new project, led by KU Leuven, has two main objectives: to improve the preservation of the remains and to genetically verify their identities. The Laboratory for Human Genetic Genealogy previously carried out a similar analysis on the skeleton of William II of Holland (1227–1256), King of the Romans and grandson of Henry I.

Source: KU Leuven – University of Leuven