1253 grant of Sicily to Edmund of Lancaster. Alexander's successor, Pope Urban IV, was determined to put an end to the Emperor's rule in Italy. He sent his notary, Albert of Parma, to Paris to negotiate with Louis IX for Charles to be placed on the Sicilian throne. Charles met with the Pope's envoy in early 1262. Taking advantage of Charles's absence, Boniface of Castellane stirred up a new revolt in Provence. The burghers of Marseilles expelled Charles's officials, but Barral of Baux stopped the spread of the rebellion before Charles's return. Charles renounced Ventimiglia in favour of the Republic of Genoa to secure her neutrality. He defeated the rebels and forced Castellane into exile. The mediation of James I of Aragon brought about a settlement with Marseilles: its fortifications were dismantled and the townspeople surrendered their arms, but the town retained its autonomy. Conquest of the Regno Louis IX decided to support Charles's military campaign in Italy in May 1263. Pope Urban IV promised to proclaim a crusade against Manfred, while Charles pledged that he would not accept any offices in the Italian towns. Manfred staged a coup in Rome, but the Guelphs elected Charles senator (or the head of the civil government of Rome). He accepted the office, at which a group of cardinals requested that the Pope revoke the agreement with him, but the Pope, being otherwise defenceless against Manfred, could not break with Charles. In the spring of 1264 Cardinals Simon of Brie and Guy Foulquois were sent to France to reach a compromise and start raising support for the crusade. Charles sent troops to Rome to protect the Pope against Manfred's allies. At Foulquois' request, Charles's sister-in-law Margaret (who had not abandoned her claims to her dowry) pledged that she would not take actions against Charles during his absence. Foulquois also persuaded the French and Provençal prelates to offer financial support for the crusade. Pope Urban died before the final agreement was concluded. Charles made arrangements for his campaign against Sicily during the interregnum; he concluded agreements to secure his army's route across Lombardy and had the leaders of the Provençal rebels executed. Foulquois was elected pope in February 1265; he soon confirmed Charles's senatorship and urged him to come to Rome. Charles agreed that he would hold the Kingdom of Sicily as the popes' vassal for an annual tribute of 8,000 ounces of gold.