The History of Rome

Every freeholder from the eighteenth to the sixtieth year of his age, including children in the household of freeholder fathers, without distinction of birth, was under obligation of service, so that even the manumitted slave had to serve, if in an exceptional case he had come into possession of landed  property. The Latins also possessing land - others from without were not allowed to acquire Roman soil - were called in to service, so far as they had, as was beyond doubt the case with most of them, taken up their abode on Roman territory. The body of men liable to serve was distributed, according to the size of their portions of land, into those bound to full service or the possessors of a full hide[6], who were obliged to appear in complete armour and in so far formed pre-eminently the war army (classis), and the four following ranks of smaller landholders - the possessors respectively of three fourths, of a half, of a quarter, or of an eighth of a whole farm - from whom was required fulfilment of service, but not equipment in complete armour, and they thus had a position below the full rate (infra classem). As the land happened to be at that time apportioned, almost the half of the farms were full hides, while each of the classes possessing respectively three-fourths, the half, and the quarter of a hide, amounted to scarcely an eighth of the freeholders, and those again holding an eighth of a hide amounted to fully an eighth. It was accordingly laid down as a rule that in the case of the infantry the levy should be in the proportion of eighty holders of a full hide, twenty from each of the three next ranks, and twenty-eight from the last.

Cavalry

The cavalry was similarly dealt with. The number of divisions in it was tripled, and the only difference in this case was that the six divisions already existing with the old names (Tities, Ramnes, Luceresprimi and secundi) were left to the patricians, while the twelve new divisions were formed chiefly from the non-burgesses. The reason for this difference is probably to be sought in the fact that at that period the infantry were formed anew for each campaign and discharged on their return home, whereas the cavalry with their horses were on military grounds kept together also in time of peace, and held their regular drills, which continued to subsist as festivals of the Roman equites down to the latest times[7]. Accordingly the squadrons once constituted were allowed, even under this reform, to keep their ancient names. In order to make the cavalry accessible to every burgess, the unmarried women and orphans under age, so far as they had possession of land, were bound instead of personal service to provide the horses for particular troopers (each trooper had two of them), and to furnish them with fodder. On the whole there was one horseman to nine foot-soldiers; but in actual service the horsemen were used more sparingly.

The non-freeholders (adcensi, people standing at the side of the list of those owing military service) had to supply the army with workmen and musicians as well as with a number of substitutes who marched with the army unarmed (velati), and, when vacancies occurred in the field, took their places in the ranks equipped with the weapons of the sick or of the fallen.

Levy-Districts

To facilitate the levying of the infantry, the city was distributed into four "parts" (tribus); by which the old triple division was superseded, at least so far as concerned its local significance. These were the Palatine, which comprehended the height of that name along with the Velia; the Suburan, to which the street so named, the Carinae, and the Caelian belonged; the Esquiline; and the Colline, formed by the Quirinal and Viminal, the "hills" as contrasted with the "mounts" of the Capitol and Palatine. We have already spoken of the formation of these regions[8] and shown how they originated out of the ancient double city of the Palatine and the Quirinal. By what process it came to pass that every freeholder burgess belonged to one of those city-districts, we cannot tell; but this was now the case; and that the four regions were nearly on an equality in point of numbers, is evident from their being equally drawn upon in the levy. This division, which had primary reference to the soil alone and applied only inferentially to those who possessed it, was merely for administrative purposes, and in particular never had any religious significance attached to it; for the fact that in each of the city-districts there were six chapels of the enigmatical Argei no more confers upon them the character of ritual districts than the erection of an altar to the Lares in each street implies such a character in the streets.