ABSTRACT
On 20 December 1463 Hupert von Heinsberg, a Hospitaller priest, made a foundation for the celebration of mass in his commandery's chapel at Cologne. The foundation was probably linked to another – that of a fraternity in honours of St John the Baptist. Mass would be celebrated at an altar to be erected for the purpose. Hupert von Heinsberg, a Hospitaller priest and for the years 1469–99 commander of the house in Cologne, was the son of a furrier of Cologne, Volquin von Heinsberg, and his wife Margarete von Alpen. The brethern and benefactors of the Hospitaller commandery had originally built another altar in the chapel, near the tomb of St Cordula in the middle of the nave. But once the fraternity altar was erected, it was transferred to the newly built chapel of St John. The Hospitaller priests were responsible for these masses, which were to be celebrated invariably regularly — even in times of interdict or excommunication.
