The Archbishopric of Magdeburg was a Roman Catholic archdiocese (969–1552) and Prince-Archbishopric (1180–1680) of the Holy Roman Empire centered on the city of Magdeburg on the Elbe River. Planned since 955 and established in 968, the Roman Catholic archdiocese had de facto turned void since 1557, when the last papally confirmed prince-archbishop, the Lutheran Sigismund of Brandenburg came of age and ascended to the see and the Magdeburg Cathedral chapter had adopted Lutheranism in 1567, with most parishioners having preceded in their conversion. All his successors were only administrators of the prince-archbishopric and Lutheran too, except of the Catholic layman Leopold William of Austria (1631–1635). In ecclesiastical respect the remaining Catholics and their parishes and abbeys in the