In the classical period of Greek and Latin antiquity the reign of kings was for the most part a thing of the past; yet the stories of their lineage, titles, and pretensions suffice to prove that they too claimed to rule by divine right and to exercise superhuman powers. Hence we may without undue temerity assume that the King of the Wood at Nemi, though shorn in later times of his glory and fallen on evil days, represented a long line of sacred kings who had once received not only the homage but the adoration of their subjects in return for the manifold blessings which they were supposed to dispense. What little we know of the functions of Diana in the Arician grove seems to prove that she was here conceived as a goddess of fertility, and particularly as a divinity of childbirth. It is reasonable, therefore, to suppose that in the discharge of these important duties she was assisted by her priest, the two figuring as King and Queen of the Wood in a solemn marriage, which was intended to make the earth gay with the blossoms of spring and the fruits of autumn, and to gladden the hearts of men and women with healthful offspring.
If the priest of Nemi posed not merely as a king, but as a god of the grove, we have still to ask, What deity in particular did he personate? The answer of antiquity is that he represented Virbius, the consort or lover of Diana. But this does not help us much, for of Virbius we know little more than the name. A clue to the mystery is perhaps supplied by the Vestal fire which burned in the grove. For the perpetual holy fires of the Aryans in Europe appear to have been commonly kindled and fed with oak-wood, and in Rome itself, not many miles from Nemi, the fuel of the Vestal fire consisted of oaken sticks or logs, as has been proved by a microscopic analysis of the charred embers of the Vestal fire, which were discovered by Commendatore G. Boni in the course of the memorable excavations which he conducted in the Roman forum at the end of the nineteenth century. But the ritual of the various Latin towns seems to have been marked by great uniformity; hence it is reasonable to conclude that wherever in Latium a Vestal fire was maintained, it was fed, as at Rome, with wood of the sacred oak. If this was so at Nemi, it becomes probable that the hallowed grove there consisted of a natural oak-wood, and that therefore the tree which the King of the Wood had to guard at the peril of his life was itself an oak; indeed, it was from an evergreen oak, according to Virgil, that Aeneas plucked the Golden Bough. Now the oak was the sacred tree of Jupiter, the supreme god of the Latins. Hence it follows that the King of the Wood, whose life was bound up in a fashion with an oak, personated no less a deity than Jupiter himself. At least the evidence, slight as it is, seems to point to this conclusion. The old Alban dynasty of the Silvii or Woods, with their crown of oak leaves, apparently aped the style and emulated the powers of Latian Jupiter, who dwelt on the top of the Alban Mount. It is not impossible that the King of the Wood, who guarded the sacred oak a little lower down the mountain, was the lawful successor and representative of this ancient line of the Silvii or Woods. At all events, if I am right in supposing that he passed for a human Jupiter, it would appear that Virbius, with whom legend identified him, was nothing but a local form of Jupiter, considered perhaps in his original aspect as a god of the greenwood.
The hypothesis that in later times at all events the King of the Wood played the part of the oak god Jupiter, is confirmed by an examination of his divine partner Diana. For two distinct lines of argument converge to show that if Diana was a queen of the woods in general, she was at Nemi a goddess of the oak in particular. In the first place, she bore the title of Vesta, and as such presided over a perpetual fire, which we have seen reason to believe was fed with oak wood. But a goddess of fire is not far removed from a goddess of the fuel which burns in the fire; primitive thought perhaps drew no sharp line of distinction between the blaze and the wood that blazes. In the second place, the nymph Egeria at Nemi appears to have been merely a form of Diana, and Egeria is definitely said to have been a Dryad, a nymph of the oak. Elsewhere in Italy the goddess had her home on oak-clad mountains. Thus Mount Algidus, a spur of the Alban hills, was covered in antiquity with dark forests of oak, both of the evergreen and the deciduous sort. In winter the snow lay long on these cold hills, and their gloomy oak-woods were believed to be a favourite haunt of Diana, as they have been of brigands in modern times. Again, Mount Tifata, the long abrupt ridge of the Apennines which looks down on the Campanian plain behind Capua, was wooded of old with evergreen oaks, among which Diana had a temple. Here Sulla thanked the goddess for his victory over the Marians in the plain below, attesting his gratitude by inscriptions which were long afterwards to be seen in the temple. On the whole, then, we conclude that at Nemi the King of the Wood personated the oak-god Jupiter and mated with the oak-goddess Diana in the sacred grove. An echo of their mystic union has come down to us in the legend of the loves of Numa and Egeria, who according to some had their trysting-place in these holy woods.
To this theory it may naturally be objected that the divine consort of Jupiter was not Diana but Juno, and that if Diana had a mate at all he might be expected to bear the name not of Jupiter, but of Dianus or Janus, the latter of these forms being merely a corruption of the former. All this is true, but the objection may be parried by observing that the two pairs of deities, Jupiter and Juno on the one side, and Dianus and Diana, or Janus and Jana, on the other side, are merely duplicates of each other, their names and their functions being in substance and origin identical. With regard to their names, all four of them come from the same Aryan root DI, meaning “bright,” which occurs in the names of the corresponding Greek deities, Zeus and his old female consort Dione. In regard to their functions, Juno and Diana were both goddesses of fecundity and childbirth, and both were sooner or later identified with the moon. As to the true nature and functions of Janus the ancients themselves were puzzled; and where they hesitated, it is not for us confidently to decide. But the view mentioned by Varro that Janus was the god of the sky is supported not only by the etymological identity of his name with that of the sky-god Jupiter, but also by the relation in which he appears to have stood to Jupiter’s two mates, Juno and Juturna. For the epithet Junonian bestowed on Janus points to a marriage union between the two deities; and according to one account Janus was the husband of the water-nymph Juturna, who according to others was beloved by Jupiter. Moreover, Janus, like Jove, was regularly invoked, and commonly spoken of under the title of Father. Indeed, he was identified with Jupiter not merely by the logic of the learned St. Augustine, but by the piety of a pagan worshipper who dedicated an offering to Jupiter Dianus. A trace of his relation to the oak may be found in the oakwoods of the Janiculum, the hill on the right bank of the Tiber, where Janus is said to have reigned as a king in the remotest ages of Italian history.
Thus, if I am right, the same ancient pair of deities was variously known among the Greek and Italian peoples as Zeus and Dione, Jupiter and Juno, or Dianus (Janus) and Diana (Jana), the names of the divinities being identical in substance, though varying in form with the dialect of the particular tribe which worshipped them. At first, when the peoples dwelt near each other, the difference between the deities would be hardly more than one of name; in other words, it would be almost purely dialectical. But the gradual dispersion of the tribes, and their consequent isolation from each other, would favour the growth of divergent modes of conceiving and worshipping the gods whom they had carried with them from their old home, so that in time discrepancies of myth and ritual would tend to spring up and thereby to convert a nominal into a real distinction between the divinities. Accordingly when, with the slow progress of culture, the long period of barbarism and separation was passing away, and the rising political power of a single strong community had begun to draw or hammer its weaker neighbours into a nation, the confluent peoples would throw their gods, like their dialects, into a common stock; and thus it might come about that the same ancient deities, which their forefathers had worshipped together before the dispersion, would now be so disguised by the accumulated effect of dialectical and religious divergencies that their original identity might fail to be recognised, and they would take their places side by side as independent divinities in the national pantheon.
This duplication of deities, the result of the final fusion of kindred tribes who had long lived apart, would account for the appearance of Janus beside Jupiter, and of Diana or Jana beside Juno in the Roman religion. At least this appears to be a more probable theory than