The senate was not affected by the reform of the constitution in the same way as the community. The previously existing college of elders not only continued exclusively patrician, but retained also its essential prerogatives - the right of appointing the interrex, and of confirming or rejecting the resolutions adopted by the community as constitutional or unconstitutional. In fact these prerogatives were enhanced by the reform of the constitution, because the appointment of the magistrates also, which fell to be made by election of the community, was thenceforth subject to the confirmation or rejection of the patrician senate. In cases of appeal alone its confirmation, so far as we know, was never deemed requisite, because in these the matter at stake was the pardon of the guilty and, when this was granted by the sovereign assembly of the people, any cancelling of such an act was wholly out of the question.
But, although by the abolition of the monarchy the constitutional rights of the patrician senate were increased rather than diminished, there yet took place - and that, according to tradition, immediately on the abolition of the monarchy - so far as regards other affairs which fell to be discussed in the senate and admitted of a freer treatment, an enlargement of that body, which brought into it plebeians also, and which in its consequences led to a complete remodelling of the whole. From the earliest times the senate had acted also, although not solely or especially, as a state-council; and, while probably even in the time of the kings it was not regarded as unconstitutional for non-senators in this case to take part in the assembly[12], it was now arranged that for such discussions there should be associated with the patrician senate (-patres-) a number of non-patricians "added to the roll" (conscripti). This did not at all put them on a footing of equality; the plebeians in the senate did not become senators, but remained members of the equestrian order, were not designated -patres-but were even now conscripti, and had no right to the badge of senatorial dignity, the red shoe[13]. Moreover, they not only remained absolutely excluded from the exercise of the magisterial prerogatives belonging to the senate (auctoritas), but were obliged, even where the question had reference merely to an advice (consilium), to rest content with the privilege of being present in silence while the question was put to the patricians in turn, and of only indicating their opinion by adding to the numbers when the division was taken - voting with the feet (pedibus in sententiam ire, pedarii) as the proud nobility expressed it. Nevertheless, the plebeians found their way through the new constitution not merely to the Forum, but also to the senate-house, and the first and most difficult step towards equality of rights was taken in this quarter also.
Otherwise there was no material change in the arrangements affecting the senate. Among the patrician members a distinction of rank soon came to be recognized, especially in putting the vote: those who were proximately designated for the supreme magistracy, or who had already administered it, were entered on the list and were called upon to vote before the rest; and the position of the first of them, the foreman of the senate (princeps senatus) soon became a highly coveted place of honour. The consul in office, on the other hand, no more ranked as a member of senate than did the king, and therefore in taking the votes did not include his own. The selection of the members - both of the narrower patrician senate and of those merely added to the roll - fell to be made by the consuls just as formerly by the kings; but the nature of the case implied that, while the king had still perhaps some measure of regard to the representation of the several clans in the senate, this consideration was of no account so far as concerned the plebeians, among whom the clan-organization was but imperfectly developed, and consequently the relation of the senate to that organization in general fell more and more into abeyance. We have no information that the electing consuls were restricted from admitting more than a definite number of plebeians to the senate; nor was there need for such a regulation, because the consuls themselves belonged to the nobility. On the other hand probably from the outset the consul was in virtue of his very position practically far less free, and far more bound by the opinions of his order and by custom, in the appointment of senators than the king. The rule in particular, that the holding of the consulship should necessarily be followed by admission to the senate for life, if, as was probably the case at this time, the consul was not yet a member of it at the time of his election, must have in all probability very early acquired consuetudinary force. In like manner it seems to have become early the custom not to fill up the senators' places immediately on their falling vacant, but to revise and complete the roll of the senate on occasion of the census, consequently, as a rule, every fourth year; which also involved a not unimportant restriction on the authority entrusted with the selection. The whole number of the senators remained as before, and in this the -conscripti- were also included; from which fact we are probably entitled to infer the numerical falling off of the patriciate[14].
We thus see that in the Roman commonwealth, even on the conversion of the monarchy into a republic, the old was as far as possible retained. So far as a revolution in a state can be conservative at all, this one was so; not one of the constituent elements of the commonwealth was really overthrown by it. This circumstance indicates the character of the whole movement. The expulsion of the Tarquins was not, as the pitiful and deeply falsified accounts of it represent, the work of a people carried away by sympathy and enthusiasm for liberty, but the work of two great political parties already engaged in conflict, and clearly aware that their conflict would steadily continue - the old burgesses and the metoeci - who, like the English Whigs and Tories in 1688, were for a moment united by the common danger which threatened to convert the commonwealth into the arbitrary government of a despot, and differed again as soon as the danger was over. The old burgesses could not get rid of the monarchy without the cooperation of the new burgesses; but the new burgesses were far from being sufficiently strong to wrest the power out of the hands of the former at one blow. Compromises of this sort are necessarily limited to the smallest measure of mutual concessions obtained by tedious bargaining; and they leave the future to decide which of the constituent elements shall eventually preponderate, and whether they will work harmoniously together or counteract one another. To look therefore merely to the direct innovations, possibly to the mere change in the duration of the supreme magistracy, is altogether to mistake the broad import of the first Roman revolution: its indirect effects were by far the most important, and vaster doubtless than even its authors anticipated.
This, in short, was the time when the Roman burgess-body in the later sense of the term originated. The plebeians had hitherto been metoeci who were subjected to their share of taxes and burdens, but who were nevertheless in the eye of the law really nothing but tolerated aliens, between whose position and that of foreigners proper it may have seemed hardly necessary to draw a definite line of distinction. They were now enrolled in the lists as burgesses liable to military service, and, although they were still far from being on a footing of legal equality - although the old burgesses still remained exclusively entitled to perform the acts of authority constitutionally pertaining to the council of elders, and exclusively eligible to the civil magistracies and priesthoods, nay even by preference entitled to participate in the usufructs of burgesses, such as the joint use of the public pasture - yet the first and most difficult step towards complete equalization was gained from the time when the plebeians no longer served merely in the common levy, but also voted in the common assembly and in the common council when its opinion was asked, and the head and back of the poorest metoikos were as well protected by the right of appeal as those of the noblest of the old burgesses. One consequence of this amalgamation of the patricians and plebeians in a new corporation of Roman burgesses was the conversion of the old burgesses into a clan-nobility, which was incapable of receiving additions or even of filling up its own ranks, since the nobles no longer possessed the right of passing decrees in common assembly and the adoption of new families into the nobility by decree of the community appeared still less admissible. Under the kings the ranks of the Roman nobility had not been thus closed, and the admission of new clans was no very rare occurrence: now this genuine characteristic of patricianism made its appearance as the sure herald of the speedy loss of its political privileges and of its exclusive estimation in the community. The exclusion of the plebeians from all public magistracies and public priesthoods - while they were admissible to the position of officers and senators - and the maintenance, with perverse obstinacy, of the legal impossibility of marriage between old burgesses and plebeians, further impressed on the patriciate from the outset the stamp of an exclusive and wrongly privileged aristocracy. A second consequence of the new union of the burgesses must have been a more definite regulation of the right of settlement, with reference both to the Latin confederates and to other states. It became necessary - not so much on account of the right of suffrage in the centuries (which indeed belonged only to the freeholder) as on account of the right of appeal, which was intended to be conceded to the plebeian, but not to the foreigner dwelling for a time or even permanently in Rome - to express more precisely the conditions of the acquisition of plebeian rights, and to mark off the enlarged burgess-body in its turn from those who were now the non-burgesses. To thisepoch therefore we may trace back - in the views and feelings of the people - both the invidiousness of the distinction between patricians and plebeians, and the strict and haughty line of demarcation between cives Romani and aliens. But the former civic distinction was in its nature transient, while the latter political one was permanent; and the sense of political unity and rising greatness, which was thus implanted in the heart of the nation, was expansive enough first to undermine and then to carry away with its mighty current those paltry distinctions.