This government, as will be seen hereafter, occasioned the ruin of the nobility; for the people by various causes excluded them from all participation in it, and then trampled upon them without respect. The nobles at first, owing to their divisions among themselves, made no opposition; and each being anxious to rob the other of influence in the state, they lost it altogether. To this government a palace was given, in which they were to reside constantly, and all requisite officers were appointed; it having been previously the custom of councils and magistrates to assemble in churches. At first they were only called Priors, but to increase their distinction the word signori, or lords, was soon afterward adopted. The Florentines remained for some time in domestic quiet, during which they made war with the Aretins for having expelled the Guelphs, and obtained a complete victory over them at Campaldino. The city being increased in riches and population, it was found expedient to extend the walls, the circle of which was enlarged to the extent it at present remains, although its diameter was previously only the space between the old bridge and the church of St. Lorenzo.
Wars abroad and peace within the city had caused the Guelph and Ghibelline factions to become almost extinct; and the only party feeling which seemed occasionally to glow, was that which naturally exists in all cities between the higher classes and the people; for the latter, wishing to live in conformity with the laws, and the former to be themselves the rulers of the people, it was not possible for them to abide in perfect amity together. This ungenial disposition, while their fear of the Ghibellines kept them in order, did not discover itself, but no sooner were they subdued than it broke forth, and not a day passed without some of the populace being injured, while the laws were insufficient to procure redress, for every noble with his relations and friends defended himself against the forces of the Priors and the Capitano. To remedy this evil, the leaders of the Arts' companies ordered that every Signory at the time of entering upon the duties of office should appoint a Gonfalonier of Justice, chosen from the people, and place a thousand armed men at his disposal divided into twenty companies of fifty men each, and that he, with his gonfalon or banner and his forces, should be ready to enforce the execution of the laws whenever called upon, either by the Signors themselves or the Capitano. The first elected to this high office was Ubaldo Ruffoli. This man unfurled his gonfalon, and destroyed the houses of the Galletti, on account of a member of that family having slain one of the Florentine people in France. The violent animosities among the nobility enabled the companies of the Arts to establish this law with facility; and the former no sooner saw the provision which had been made against them than they felt the acrimonious spirit with which it was enforced. At first it impressed them with greater terror, but they soon after returned to their accustomed insolence, for one or more of their body always making part of the Signory, gave them opportunities of impeding the Gonfalonier, so that he could not perform the duties of his office. Besides this, the accuser always required a witness of the injury he had received, and no one dared to give evidence against the nobility. Thus in a short time Florence again fell into the same disorders as before, and the tyranny exercised against the people was as great as ever; for the decisions of justice were either prevented or delayed, and sentences were not carried into execution.
In this unhappy state, the people not knowing what to do, Giano della Bella, of a very noble family, and a lover of liberty, encouraged the heads of the Arts to reform the constitution of the city; and by his advice it was ordered that the Gonfalonier should reside with the Priors, and have four thousand men at his command. They deprived the nobility of the right to sit in the Signory. They condemned the associates of a criminal to the same penalty as himself, and ordered that public report should be taken as evidence. By these laws, which were called the ordinations of justice, the people acquired great influence, and Giano della Bella not a small share of trouble; for he was thoroughly hated by the great, as the destroyer of their power, while the opulent among the people envied him, for they thought he possessed too great authority. This became very evident upon the first occasion that presented itself.
It happened that a man from the class of the people was killed in a riot, in which several of the nobility had taken a part, and among the rest Corso Donati, to whom, as the most forward of the party, the death was attributed. He was, therefore, taken by the captain of the people, and whether he was really innocent of the crime or the Capitano was afraid of condemning him, he was acquitted. This acquittal displeased the people so much, that, seizing their arms, they ran to the house of Giano della Bella, to beg that he would compel the execution of those laws which he had himself made. Giano, who wished Corso to be punished, did not insist upon their laying down their arms, as many were of opinion he ought to have done, but advised them to go to the Signory, complain of the fact, and beg that they would take it into consideration. The people, full of wrath, thinking themselves insulted by the Capitano and abandoned by Giano della Bella, instead of going to the Signory went to the palace of the Capitano, of which they made themselves masters, and plundered it.