new claimant, Hermann of Luxembourg, was put forward in August 1081, but his personality was not suitable for a leader of the Gregorian party in Germany, and the power of Henry IV was at its peak. The pope's chief military supporter, Matilda of Tuscany, blocked Henry's armies from the western passages over the Apennines, so he had to approach Rome from Ravenna. Rome surrendered to the German king in 1084, and Gregory thereupon retired into the exile of the Castel Sant'Angelo. Gregory refused to entertain Henry's overtures, although the latter promised to hand over Guibert as a prisoner, if the sovereign pontiff would only consent to crown him emperor. Gregory, however, insisted as a necessary preliminary that Henry should appear before a Council and do penance. The emperor, while pretending to submit to these terms, tried hard to prevent the meeting of the bishops. A small number assembled nonetheless, and, in accordance with their wishes, Gregory again excommunicated Henry. Henry, upon receipt of this news, again entered Rome on 21 March to see that his supporter, Archbishop Guibert of Ravenna, was enthroned as Pope Clement III on 24 March 1084. Henry was crowned emperor by his creature, but Robert Guiscard, with whom in the meantime Gregory had formed an alliance, was already marching on the city. Henry was compelled to flee towards Civita Castellana. Exile from Rome The pope was liberated, but after the Roman people became incensed by the excesses of his Norman allies, he was compelled to withdraw to Monte Cassino, and later to the castle of Salerno by the sea, where he died on 25 May 1085. Three days before his death, he withdrew all the censures of excommunication that he had pronounced, except those against the two chief offenders—Henry and Guibert. Papal policy to the rest of Europe England In 1076, Gregory appointed Dol Euen, a monk of Saint-Melaine of Rennes, as bishop of Dol, rejecting both the incumbent, Iuthael, who had the support of William the Conqueror, who had recently been conducting military operations in north-eastern Brittany, and Gilduin, the candidate of the nobles in Dol opposing William. Gregory rejected Iuthael because he was notorious for simony and Guilden as too young. Gregory also bestowed on Dol Euen the pallium of a metropolitan archbishop, on the condition that he would submit to the judgment of the Holy See when the long-standing case of the right