The Lucchese being threatened with the anger of the count, for affording refuge to the Guelphs after the battle of the Arbia, could allow them to remain no longer; so leaving Lucca, they went to Bologna, from whence they were called by the Guelphs of Parma against the Ghibellines of that city, where, having overcome the enemy, the possessions of the latter were assigned to them; so that having increased in honors and riches, and learning that Pope Clement had invited Charles of Anjou to take the kingdom from Manfred, they sent ambassadors to the pope to offer him their services. His holiness not only received them as friends, but gave them a standard upon which his insignia were wrought. It was ever after borne by the Guelphs in battle, and is still used at Florence. Charles having taken the kingdom from Manfred, and slain him, to which success the Guelphs of Florence had contributed, their party became more powerful, and that of the Ghibellines proportionately weaker. In consequence of this, those who with Count Novello governed the city, thought it would be advisable to attach to themselves, with some concession, the people whom they had previously aggravated with every species of injury; but these remedies which, if applied before the necessity came would have been beneficial, being offered when they were no longer considered favors, not only failed of producing any beneficial results to the donors, but hastened their ruin. Thinking, however, to win them to their interests, they restored some of the honors of which they had deprived them. They elected thirty-six citizens from the higher rank of the people, to whom, with two cavaliers, knights or gentlemen, brought from Bologna, the reformation of the government of the city was confided. As soon as they met, they classed the whole of the people according to their arts or trades, and over each art appointed a magistrate, whose duty was to distribute justice to those placed under him. They gave to each company or trade a banner, under which every man was expected to appear armed, whenever the city required it.
These arts were at first twelve, seven major and five minor. The minor arts were afterward increased to fourteen, so that the whole made, as at present, twenty-one. The thirty-six reformers also effected other changes for the common good.
Count Guido proposed to lay a tax upon the citizens for the support of the soldiery; but during the discussion found so much difficulty, that he did not dare to use force to obtain it; and thinking he had now lost the government, called together the leaders of the Ghibellines, and they determined to wrest from the people those powers which they had with so little prudence conceded. When they thought they had sufficient force, the thirty-six being assembled, they caused a tumult to be raised, which so alarmed them that they retired to their houses, when suddenly the banners of the Arts were unfurled, and many armed men drawn to them. These, learning that Count Guido and his followers were at St. John's, moved toward the Holy Trinity, and chose Giovanni Soldanieri for their leader. The count, on the other hand, being informed where the people were assembled, proceeded in that direction;nor did the people shun the fight, for, meeting their enemies where now stands the residence of the Tornaquinci, they put the count to flight, with the loss of many of his followers. Terrified with this result, he was afraid his enemies would attack him in the night, and that his own party, finding themselves beaten, would murder him. This impression took such hold of his mind that, without attempting any other remedy, he sought his safety rather in flight than in combat, and, contrary to the advice of the rectors, went with all his people to Prato. But, on finding himself in a place of safety, his fears fled; perceiving his error he wished to correct it, and on the following day, as soon as light appeared, he returned with his people to Florence, to enter the city by force which he had abandoned in cowardice. But his design did not succeed; for the people, who had had difficulty in expelling him, kept him out with facility; so that with grief and shame he went to the Casentino, and the Ghibellines withdrew to their villas.
The people being victorious, by the advice of those who loved the good of the republic, determined to reunite the city, and recall all the citizens as well Guelph as Ghibelline, who yet remained without. The Guelphs returned, after having been expelled six years; the recent offences of the Ghibellines were forgiven, and themselves restored to their country. They were, however, most cordially hated, both by the people and the Guelphs, for the latter could not forget their exile, and the former but too well remembered their tyranny when they were in power; the result was, that the minds of neither party became settled.
While affairs were in this state at Florence, a report prevailed that Corradino, nephew of Manfred, was coming with a force from Germany, for the conquest of Naples; this gave the Ghibellines hope of recovering power, and the Guelphs, considering how they should provide for their security, requested assistance from Charles for their defense, in case of the passage of Corradino. The coming of the forces of Charles rendered the Guelphs insolent, and so alarmed the Ghibellines that they fled the city, without being driven out, two days before the arrival of the troops.
The Ghibellines having departed, the Florentines reorganized the government of the city, and elected twelve men who, as the supreme power, were to hold their magistracy two months, and were not called Anziani or "ancients," but Buono Uomini or "good men." They also formed a council of eighty citizens, which they called the Credenza.