State Religion.—In passing to the religion of the State we enter on a later period and a more developed form of society. The loose aggregation of agricultural households gives place to the organized community with new needs and new ideals. Thus we find two prominent notes of the State influence, firstly, the adaptation of the old ideas of the household and agricultural cults to the broader needs of the city-community, especially to the new necessities of internal justice and war against external enemies; and secondly the organization of informal worship into a con sistent system. Adaptation proceeded at first naturally enough on the lines of analogy. As Janus was in the household the numen of the door, so in the State he was associated with the great gate near the corner of the forum : the Penates had their analogy in the Di Penates populi Romani Quiritium by whom the magistrates took their oath on entering office, the lar familiaris in the Lares Praestites of the community, and the genius in the new notion of the Genius populi Romani or Genius urbis Romae. But the closest and most striking analogy is seen in the cult of Vesta. The Vesta of the State was in fact the king's hearth, standing in close proximity to the Regia, the king's palace ; the Vestal Virgins, who had charge of the sacred fire, were the "king's daughters," and as such even in republican times were in the legal power of the pontifex maximus. But adaptation meant also the widening of old conceptions under the influence of reflexion. Thus, since the door is used for the double purpose of entrance and exit, the Janus of the State was represented as bifrons ("two-faced") : the thought of the door as the first part of the house to which one comes produces the more abstract idea of Janus as the "god of beginnings," in which character he had special charge of the first hour of the day, the calends of the month and the first month of the year in the later calendar. But development proceeded also on broader lines. Jupiter in the rustic-cult was a sky-god con cerned mainly with the wine festivals and associated with the sacred oak on the Capitol. Now he developed a twofold charac ter: as the receiver of the spolia opima he became associated with war, especially in the double character of the stayer of rout (Stator) and the giver of victory (Victor). As the sky-god again he was appealed to as the witness of oaths in the special capacity of Dius Fidius. In these two conceptions, justice and war, lie the germs of the later idea of Jupiter as the embodiment of the life of the Roman people, both in their internal organization and in their external relations. In much the same manner the agricul tural character of Mars became submerged by his functions as war-god. Finally, we must notice, as the sign of the union of two settlements, the inclusion of the Colline deity, Quirinus, appar ently the Mars of the originally rival community. In these three deities, Jupiter, Mars, Quirinus, we have the great triad of the earliest stage of the State religion.
Organization showed itself in the fixing of the annual calendar of festivals, the development of the character and functions of the priesthood and in a new conception of the legal relation of the gods of the State. The State now approached the gods through its duly appointed representatives, the magistrates and priests, and the private citizen was required to do no more on festival days than observe a ceremonial abstinence from work. The State religion had thus less direct connection with morality and the religious sense than the worship of the household, but it had its ethical value in a sense of discipline and a consecration of the spirit of patriotism.
External Influences.—The later stages represent not the spontaneous development of the genuine Roman religion, but its alteration and supersession by new cults and ideas introduced from foreign sources. Three periods may be recognized: (1) from the end of the regal epoch to the second Punic War—the period of contact with the peoples of Italy ; (2) from the second Punic War to the end of the Republic—the period of contact with Greece and the Orient; (3) the imperial epoch, opening with a revival of old religious notions and later marked by the official worship of the deified emperors and the wide influence of oriental cults.
Italian Influence.—By the end of the regal period Rome was a really developed city-state. There was a large artisan class, excluded from the old patrician gentes and therefore from the State cult. At the same time the beginnings of com merce had opened relations with neighbouring peoples. The con sequence was the introduction of certain new deities, the di novensides, from external sources, and the birth of new concep tions of the gods and their worship. We may distinguish three main influences : (a) Etruria.—The last three kings of Rome were Etruscans and Etruscan influence under their rule was strong. From Etruria came Minerva, who, as the goddess of handicraft and protectress of the artisan guilds, was established in a temple on the Aventine. Soon a new Etruscan triad, Jupiter, Juno and Minerva, was en shrined on the Capitol in a magnificent new temple built by Etruscan workmen and decorated in the Etruscan manner. In this temple the deities were represented by images.
(b) Latium.—Secondly, in war and peace Rome formed rela tions with her neighbours of Latium, and, as a sign of the Latin league which resulted, the cult of Diana was brought from Aricia and established on the Aventine in the commune Latinorum Di anae templum; about the same time the temple of luppiter Latiaris was built on the Alban mount, its resemblance in style to the Capitoline temple pointing to Rome's hegemony. Latin cults were introduced even inside the pomoerium, the old city limits, the worship of Hercules, which came from Tibur in connection with commerce, was established at the Great Altar in the forum boarium, and the Tusculan cult of Castor as the patron of cavalry found a home close to the forum Romanum.
(c) Magna Graecia.—Later on contact with the cities of Magna Graecia brought about the wide-reaching introduction of the Sibylline books. They came from Cumae and were placed in the Capitoline temple under the care of a special commission; their "oracles," which were referred to in time of great national stress, recommended the introduction of foreign cults. In this way were brought to Rome the Greek triad Demeter, Dionysus and Persephone, who were identified with the old Roman divini ties Ceres, Liber and Libera, Apollo, Mercury, and Aesculapius Dis and Proserpina, with their strange chthonic associations and night ritual. With new deities came new modes of worship: the "Greek ritual" in which, contrary to Roman usage, the worship per's head was unveiled, the lectisternium (q.v.), an elaborate form of the "banquet of the gods" and the supplicatio, an appeal to the gods in which the whole people took part. In this period, then, we find first a legitimate extension of cults corresponding to the needs of the growing community and secondly a religious restlessness and a consequent tendency to more dramatic forms of worship.