At this time there were three popes, Gregory, Benedict, and Giovanni, which kept the church weak and in disrepute. The city of Constance, in Germany, was appointed for the holding of the council, contrary to the expectation of Pope John. And although the death of Ladislaus had removed the cause which induced the pope to call the council, still, having promised to attend, he could not refuse to go there. In a few months after his arrival at Constance he discovered his error, but it was too late; endeavoring to escape, he was taken, put into prison, and compelled to renounce the papacy. Gregory, one of the anti-popes, sent his renunciation; Benedict, the other, refusing to do the same, was condemned as a heretic; but, being abandoned by his cardinals, he complied, and the council elected Oddo, of the Colonnesi family, pope, by the title of Martin V. Thus the church was united under one head, after having been divided by many pontiffs. Filippo Visconti was, as we have said, in the fortress of Pavia. But Fazino Cane, who in the affairs of Lombardy had become lord of Vercelli, Alessandria, Novara, and Tortona, and had amassed great riches, finding his end approach, and having no children, left his wife Beatrice heiress of his estates, and arranged with his friends that a marriage should be effected between her and Filippo. By this union Filippo became powerful, and reacquired Milan and the whole of Lombardy. By way of being grateful for these numerous favors, as princes commonly are, he accused Beatrice of adultery and caused her to be put to death. Finding himself now possessed of greater power, he began to think of warring with Tuscany and of prosecuting the designs of Giovanni Galeazzo, his father.