antipope clement iii antipope gregory viii arnulf of carinthia berengar i of italy bologna carolingian empire charlemagne charles the bald charles the fat concise list of roman emperors confederation of the rhine conrad i constantinian dynasty double-headed eagle duchy of spoleto early middle ages emperor feudalism flavian dynasty france gallic empire german language germany guy iii of spoleto henry the fowler holy roman empire imperator imperial regalia investiture controversy julio-claudian dynasty julius nepos king of the romans kingdom of germany lambert ii of spoleto list of byzantine emperors list of german monarchs list of roman emperors lothair i lothair ii of lotharingia louis ii of italy louis the blind louis the pious napoleonic wars nervan-antonian dynasty papal appointment pope pope adrian iv pope benedict iv pope benedict viii pope celestine iii pope clement ii pope clement vii pope formosus pope gregory v pope gregory vii pope honorius iii pope innocent ii pope innocent iii pope john viii pope john x pope john xii pope john xiii pope john xix pope leo iii pope leo iv pope nicholas v pope paschal i pope paschal ii pope stephen v prince-elector roman catholic church roman emperor roman empire rome sciarra colonna severan dynasty state tetrarchy translatio imperii western roman empire wikimedia commons