Bonn Minster (German: Bonner Münster) is a Roman Catholic church in Bonn. It is one of Germany's oldest churches, having been built between the 11th and 13th centuries. At one point the church served as the de facto cathedral for the Archbishopric of Cologne, because it is the major church of what was then the Archbishop-Elector's residence. It is now a minor basilica. It served as the inspiration for the Kaiser Wilhelm Memorial Church in Berlin, as Kaiser Wilhelm II had studied in Bonn.