In the time of Otho III. there had come into Italy a man called Ezelin, who, remaining in the country, had a son, and he too had a son named Ezelin. This person, being rich and powerful, took part with Frederick, who, as we have said, was at enmity with the pope; Frederick, at the instigation and with the assistance of Ezelin, took Verona and Mantua, destroyed Vicenza, occupied Padua, routed the army of the united cities, and then directed his course towards Tuscany. Ezelin, in the meantime, had subdued the whole of the Trevisian March, but could not prevail against Ferrara, which was defended by Azone da Este and the forces which the pope had in Lombardy; and, as the enemy were compelled to withdraw, the pope gave Ferrara in fee to this Azone, from whom are descended those who now govern that city. Frederick halted at Pisa, desirous of making himself lord of Tuscany; but, while endeavoring to discover what friends and foes he had in that province, he scattered so many seeds of discord as occasioned the ruin of Italy; for the factions of the Guelphs and Ghibellines multiplied,--those who supported the church taking the name of Guelphs, while the followers of the emperor were called Ghibellines, these names being first heard at Pistoia. Frederick, marching from Pisa, assailed and wasted the territories of the church in a variety of ways; so that the pope, having no other remedy, unfurled against him the banner of the cross, as his predecessor had done against the Saracens. Frederick, that he might be suddenly abandoned by his people, as Frederick Barbarossa and others had been, took into his pay a number of Saracens; and to bind them to him, and establish in Italy a firm bulwark against the church, without fear of papal maledictions, he gave them Nocera in the kingdom of Naples, that, having a refuge of their own, they might be placed in greater security. The pontificate was now occupied by Innocent IV., who, being in fear of Frederick, went to Genoa, and thence to France, where he appointed a council to be held at Lyons, where it was the intention of Frederick to attend, but he was prevented by the rebellion of Parma: and, being repulsed, he went into Tuscany, and from thence to Sicily, where he died, leaving his son Conrad in Suabia; and in Puglia, Manfred, whom he had created duke of Benevento, born of a concubine. Conrad came to take possession of the kingdom, and having arrived at Naples, died, leaving an infant son named Corradino, who was then in Germany. On this account Manfred occupied the state, first as guardian of Corradino, but afterward, causing a report to be circulated that Corradino had died, made himself king, contrary to the wishes of both the pope and the Neapolitans, who, however, were obliged to submit.