These distinctions may perhaps have already existed partially in the time of the patrician government, and, so long as families of higher and humbler rank were distinguished within the patriciate, may have served as external insignia for the former; but they certainly only acquired political importance in consequence of the change of constitution in 387, by which the plebeian families that attained the consulate were placed on a footing of equal privilege with the patrician families, all of whom were now probably entitled to carry images of their ancestors. Moreover, it was now settled that the offices of state to which these hereditary privileges were attached should include neither the lower nor the extraordinary magistracies nor the tribunate of the plebs, but merely the consulship, the praetorship which stood on the same level with it[7], and the curule aedileship, which bore a part in the administration of public justice and consequently in the exercise of the sovereign powers of the state[8]. Although this plebeian nobility, in the strict sense of the term, could only be formed after the curule offices were opened to plebeians, yet it exhibited in a short time, if not at the very first, a certain compactness of organization - doubtless because such a nobility had long been prefigured in the old senatorial plebeian families. The result of the Licinian laws in reality therefore amounted nearly to what we should now call the creation of a batch of peers. Now that the plebeian families ennobled by their curule ancestors were united into one body with the patrician families and acquired a distinctive position and distinguished power in the commonwealth, the Romans had again arrived at the point whence they had started; there was once more not merely a governing aristocracy and a hereditary nobility - both of which in fact had never disappeared - but there was a governing hereditary nobility, and the feud between the gentes in possession of the government and the commons rising in revolt against the gentes could not but begin afresh. And matters very soon reached that stage. The nobility was not content with its honorary privileges which were matters of comparative indifference, but strove after separate and sole political power, and sought to convert the most important institutions of the state - the senate and the equestrian order - from organs of the commonwealth into organs of the plebeio-patrician aristocracy.

The dependence de jure of the Roman senate of the republic, more especially of the larger patricio-plebeian senate, on the magistracy had rapidly become lax, and had in fact been converted into independence. The subordination of the public magistracies to the state-council, introduced by the revolution of 244[9]; the transference of the right of summoning men to the senate from the consul to the censor[10]; lastly, and above all, the legal recognition of the right of those who had been curule magistrates to a seat and vote in the senate[11], had converted the senate from a council summoned by the magistrates and in many respects dependent on them into a governing corporation virtually independent, and in a certain sense filling up its own ranks; for the two modes by which its members obtained admission - election to a curule office and summoning by the censor - were both virtually in the power of the governing board itself. The burgesses, no doubt, at this epoch were still too independent to allow the entire exclusion of non-nobles from the senate, and the nobility were perhaps still too judicious even to wish for this; but, owing to the strictly aristocratic gradations in the senate itself - in which those who had been curule magistrates were sharply distinguished, according to their respective classes of consulares, praetorii, and aedilicii, from the senators who had not entered the senate through a curule office and were therefore excluded from debate - the non-nobles, although they probably sat in considerable numbers in the senate, were reduced to an insignificant and comparatively uninfluential position in it, and the senate became substantially a mainstay of the nobility.

The institution of the equites was developed into a second, less important but yet far from unimportant, organ of the nobility. As the new hereditary nobility had not the power to usurp sole possession of the comitia, it necessarily became in the highest degree desirable that it should obtain at least a separate position within the body representing the community. In the assembly of the tribes there was no method of managing this; but the equestrian centuries under the Servian organization seemed as it were created for the very purpose. The 1800 horses which the community furnished[12] were constitutionally disposed of likewise by the censors. It was, no doubt, the duty of these to select the equites on military grounds and at their musters to insist that all horsemen incapacitated by age or otherwise, or at all unserviceable, should surrender their public horse; but the very nature of the institution implied that the equestrian horses should be given especially to men of means, and it was not at all easy to hinder the censors from looking to genteel birth more than to capacity, and from allowing men of standing who were once admitted, senators particularly, to retain their horse beyond the proper time. Perhaps it was even fixed by law that the senator might retain it as long as he wished. Accordingly it became at least practically the rule for the senators to vote in the eighteen equestrian centuries, and the other places in these were assigned chiefly to the young men of the nobility. The military system, of course, suffered from this not so much through the unfitness for effective service of no small part of the legionary cavalry, as through the destruction of military equality to which the change gave rise, inasmuch as the young men of rank more and more withdrew from service in the infantry. The closed aristocratic corps of the equites proper came to set the tone for the whole legionary cavalry, taken from the citizens who were of highest position by descent and wealth. This enables us in some degree to understand why the equites during the Sicilian war refused to obey the order of the consul Gaius Aurelius Cotta that they should work at the trenches with the legionaries (502), and why Cato, when commander-in-chief of the army in Spain, found himself under the necessity of addressing a severe reprimand to his cavalry. But this conversion of the burgess-cavalry into a mounted guard of nobles redounded not more decidedly to the injury of the commonwealth than to the advantage of the nobility, which acquired in the eighteen equestrian centuries a suffrage not merely separate but giving the tone to the rest.

Of a kindred character was the formal separation of the places assigned to the senatorial order from those occupied by the rest of the multitude as spectators at the national festivals. It was the great Scipio, who effected this change in his second consulship in 560. The national festival was as much an assembly of the people as were the centuries convoked for voting; and the circumstance that the former had no resolutions to pass made the official announcement of a distinction between the ruling order and the body of subjects - which the separation implied - all the more significant. The innovation accordingly met with much censure even from the ruling class, because it was simply invidious and not useful, and because it gave a very manifest contradiction to the efforts of the more prudent portion of the aristocracy to conceal their exclusive government under the forms of civil equality.