this was widely felt to be an injustice. when rudolph of swabia died on october 16 of the same year, henry began to fight to be king. in 1081 he opened the conflict against gregory in italy. gregory had now become less powerful, and thirteen cardinals stopped supporting him. rome surrendered to the german king, and guibert of ravenna was enthroned as clement iii (march 24, 1084). henry was crowned emperor by his rival, while gregory himself had to flee from rome in the company of his norman "vassal," robert guiscard.