Duke Rudolf IV was the most influential Habsburg of the fourteenth century. Despite his short life of only twenty-six years he put an enduring stamp on his dominions in terms of both culture and politics. He had St Stephen’s Cathedral in Vienna extended on a grand scale and founded the University of Vienna, the ‘Alma Mater Rudolphina’. He also had the Habsburgs elevated to the rank of archdukes on the basis of the Privilegium maius, a forged document.