An Imperial State or Imperial Estate (; , plural: ) was a part of the Holy Roman Empire with representation and the right to vote in the Imperial Diet (). Rulers of these Estates were able to exercise significant rights and privileges and were "immediate", meaning that the only authority above them was the Holy Roman Emperor. They were thus able to rule their territories with a considerable degree of autonomy. The system of imperial states replaced the more regular division of Germany into stem duchies in the early medieval period. The old Carolingian stem duchies were retained as the major divisions of Germany under the Salian dynasty, but they became increasingly obsolete during the early high medieval period under the Hohenstaufen, and they were finally abolished in 1180 by Frederick Barbarossa in favour of more numerous territorial divisions. From 1489, the imperial Estates represented in the Diet were divided into three chambers, the college of prince-electors (), the college of imperial princes () and the college of imperial cities. Counts and nobles were not directly represented in the Diet in spite of their immediate status, but were grouped into "benches" () with a single vote each. Imperial Knights had immediate status but were not represented in the Diet. Composition Imperial Estates could be either ecclesiastic or secular. The ecclesiastical Estates were led by: the three clerical Prince-electors: the Archbishops of Cologne, Mainz and Trier; Prince-Archbishops and Prince-Bishops as well as Prince-Abbots and Prince-Provosts of the Empire; Imperial Prelates, immediate Priors and Provosts; Grand Masters of military orders like the Teutonic Knights or Knights Hospitaller. The secular Estates, most notably: the four Prince-Electors of the County Palatine of the Rhine, Saxony, Brandenburg and Bohemia, later also Bavaria (replacing the Palatinate) and Hanover. Imperial Princes including Grand Dukes, Dukes, Counts Palatine, Margraves and Landgraves; Imperial Counts, Barons, and prelates; the Free and Imperial cities. Until 1582 the votes of the Free and Imperial Cities were only advisory. None of the rulers below the Holy Roman Emperor ranked as kings, with the exception of the Kings of Bohemia. The status of Estate was normally attached to a particular territory within the Empire, but there were some , or "persons with imperial statehood". Originally, the Emperor alone could grant that status, but in 1653, several restrictions on the Emperor's power were introduced. The creation of a new Estate required the assent of the