Now that civil war was organized, it pursued its course. The parties stood face to face as if drawn up for battle, each under its leaders. Restriction of the consular and extension of the tribunician power were the objects contended for on the one side; the annihilation of the tribunate was sought on the other. Legal impunity secured for insubordination, refusal to enter the ranks for the defence of the land, impeachments involving fines and penalties directed specially against magistrates who had violated the rights of the commons or who had simply provoked their displeasure, were the weapons of the plebeians; and to these the patricians opposed violence, concert with the public foes, and occasionally also the dagger of the assassin. Hand-to-hand conflicts took place in the streets, and on both sides the sacredness of the magistrate's person was violated. Many families of burgesses are said to have migrated, and to have sought more peaceful abodes in neighbouring communities; and we may well believe it. The strong patriotism of the people is obvious from the fact, not that they adopted this constitution, but that they endured it, and that the community, notwithstanding the most vehement convulsions, still held together.

The best-known incident in these conflicts of the orders is the history of Gnaeus Marcius, a brave aristocrat, who derived his surname from the storming of Corioli. Indignant at the refusal of the centuries to entrust to him the consulate in the year 263, he is reported to have proposed, according to one version, the suspension of the sales of corn from the state-stores, till the hungry people should give up the tribunate; according to another version, the direct abolition of the tribunate itself.  Impeached by the tribunes so that his life was in peril, it is said that he left the city, but only to return at the head of a Volscian army; that when he was on the point of conquering the city of his fathers for the public foe, the earnest appeal of his mother touched his conscience; and that thus he expiated his first treason by a second, and both by death. How much of this is true cannot be determined; but the story, over which the naive misrepresentations of the Roman annalists have shed a patriotic glory, affords a glimpse of the deep moral and political disgrace of these conflicts between the orders. Of a similar stamp was the surprise of the Capitol by a band of political refugees, led by a Sabine chief, Appius Herdonius, in the year 294; they summoned the slaves to arms, and it was only after a violent conflict, and by the aid of the Tusculans who hastened to render help, that the Roman burgess-force overcame the Catilinarian band.  The same character of fanatical exasperation marks other events of this epoch, the historical significance of which can no longer be apprehended in the lying family narratives; such as the predominance of the Fabian clan which furnished one of the two consuls from 269 to 275, and the reaction against it, the emigration of the Fabii from Rome, and their annihilation by the Etruscans on the Cremera (277). Still more odious was the murder of the tribune of the people, Gnaeus Genucius, who had ventured to call two consulars to account, and who on the morning of the day fixed for the impeachment was found dead in bed (281). The immediate effect of this misdeed was the Publilian law (283), one of the most momentous in its consequences with which Roman history has to deal. Two of the most important arrangements - the introduction of the plebeian assembly of tribes, and the placing of the plebiscitum on a level, although conditionally, with the formal law sanctioned by the whole community - are to be referred, the former certainly, the latter probably, to the proposal of Volero Publilius the tribune of the people in 283. The plebs had hitherto adopted its resolutions by curies; accordingly in these its separate assemblies, on the one hand, the voting had been by mere number without distinction of wealth or of freehold property, and, on the other hand, in consequence of that standing side by side on the part of the clansmen, which was implied in the very nature of the curial assembly, the clients of the great patrician families had voted with one another in the assembly of the plebeians. These two circumstances had given to the nobility various opportunities of exercising influence on that assembly, and especially of managing the election of tribunes according to their views; and both were henceforth done away by means of the new method of voting according to tribes. Of these, four had been formed under the Servian constitution for the purposes of the levy, embracing town and country alike[8]; subsequently-perhaps in the year 259 - the Roman territory had been divided into twenty districts, of which the first four embraced the city and its immediate environs, while the other sixteen were formed out of the rural territory on the basis of the clan-cantons of the earliest Roman domain[9]. To these was added - probably only in consequence of the Publilian law, and with a view to bring about the inequality, which was desirable for voting purposes, in the total number of the divisions - as a twenty-first tribe the Crustuminian, which derived its name from the place where the plebs had constituted itself as such and had established the tribunate[10]; and thenceforth the special assemblies of the plebs took place, no longer by curies, but by tribes. In these divisions, which were based throughout on the possession of land, the voters were exclusively freeholders: but they voted without distinction as to the size of their possession, and just as they dwelt together in villages and hamlets. Consequently, this assembly of the tribes, which otherwise was externally modelled on that of the curies, was in reality an assembly of the independent middle class, from which, on the one hand, the great majority of freedmen and clients were excluded as not being freeholders, and in which, on the other hand, the larger landholders had no such preponderance as in the centuries. This "meeting of the multitude" (concilium plebis) was even less a general assembly of the burgesses than the plebeian assembly by curies had been, for it not only, like the latter, excluded all the patricians, but also the plebeians who had no land; but the multitude was powerful enough to carry the point that its decree should have equal legal validity with that adopted by the centuries, in the event of its having been previously approved by the whole senate. That this last regulation had the force of established law before the issuing of the Twelve Tables, is certain; whether it was directly introduced on occasion of the Publilian plebiscitum, or whether it had already been called into existence by some other - now forgotten - statute, and was only applied to the Publilian plebiscitum cannot be any longer ascertained. In like manner it remains uncertain whether the number of tribunes was raised by this law from two to four, or whether that increase had taken place previously.

More sagacious in plan than all these party steps was the attempt of Spurius Cassius to break down the financial omnipotence of the rich, and so to put a stop to the true source of the evil. He was a patrician, and none in his order surpassed him in rank and renown. After two triumphs, in his third consulate (268), he submitted to the burgesses a proposal to have the public domain measured and to lease part of it for the benefit of the public treasury, while a further portion was to be distributed among the necessitous. In other words, he attempted to wrest the control of the public lands from the senate, and, with the support of the burgesses, to put an end to the selfish system of occupation.  He probably imagined that his personal distinction, and the equity and wisdom of the measure, might carry it even amidst that stormy sea of passion and of weakness. But he was mistaken. The nobles rose as one man; the rich plebeians took part with them; the commons were displeased because Spurius Cassius desired, in accordance with federal rights and equity, to give to the Latin confederates their share in the assignation. Cassius had to die. There is some truth in the charge that he had usurped regal power, for he had indeed endeavoured like the kings to protect the free commons against his own order. His law was buried along with him; but its spectre thenceforward incessantly haunted the eyes of the rich, and again and again it rose from the tomb against them, until amidst the conflicts to which it led the commonwealth perished.