The effect of this long rivalry might have been expected to produce in the Romans during its continuance a hearty dislike of the customs and institutions of the nation opposed to them; but almost the exact contrary was the result. It may be argued that Rome’s proved skill in government was in no small measure due to her ready adoption of all that seemed to her admirable in the nations that she overcame. Or it may be that the influence which the memory of Alexander exercised over all those who succeeded to his empire led them to imitate him in his assumption of Persian manners. The fact remains that, long before the division of the Roman Empire into East and West, the Romans displayed a taste for Oriental luxury and magnificence which seems entirely at variance with the simplicity and austerity of the republican conquerors of Carthage. It is hardly too much to say that while Alexander’s conscious aim was to make Asia Greek, the Romans, on possessing themselves of his Asiatic conquests, allowed themselves to become to a great extent “Medized,” and showed an unexpected admiration for the habits and culture of Alexander’s Persian subjects.
It may of course be said that this was in external matters only, and that the “Persian furniture” which excited Horace’s wrath[[783]] might if it stood alone be looked upon as merely a passing fashion; but the Court ceremonial introduced by Diocletian argues a steady tendency towards Persian customs and forms of government that must have been in operation for centuries. The household of a Julian Caesar was no differently arranged from that of a Roman noble of the period, and his title of Prince of the Senate showed that he was only looked upon as the first of his equals. But Diocletian was in all respects but language a Persian emperor or Shah, and his style of “Lord and God,” his diadem, his silken state dress, the elaborate ritual of his court, and the long hierarchy of its officials, were all designed to compel his subjects to recognize the fact[[784]]. As usual, the official form of religion in the Roman Empire had for some time given indications of the coming change in the form of government. The sun had always been the principal natural object worshipped by the Persians, and a high-priest of the Sun-God had sat upon the Imperial throne of Rome in the form of the miserable Heliogabalus. Only 13 years before Diocletian, Aurelian, son of another Sun-God’s priestess and as virile and rugged as his predecessor was soft and effeminate, had also made the Sun-God the object of his special devotion and of an official worship. Hence Diocletian and his colleague Galerius were assured in advance of the approval of a large part of their subjects when they took the final plunge in 307 A.D., and proclaimed Mithras, “the Unconquered Sun-God,” the Protector of their Empire[[785]].
In spite of this, however, it is very difficult to say how Mithras originally became known to the Romans. Plutarch says indeed that his cult was first introduced by the Cilician pirates who were put down by Pompey[[786]]. This is not likely to be literally true; for the summary methods adopted by these sea-robbers towards their Roman prisoners hardly gave much time for proselytism, while most of the pirates whom Pompey spared at the close of his successful operations he deported to Achaea, which was one of the few places within the Empire where the Mithraic faith did not afterwards show itself. What Plutarch’s story probably means is that the worship of Mithras first came to Rome from Asia Minor, and there are many facts which go to confirm this. M. Cumont, the historian of Mithraism, has shown that, long before the Romans set foot in Asia, there were many colonies of emigrants from Persia who with their magi or priests had settled in Asia Minor, including in that phrase Galatia, Phrygia, Lydia, and probably Cilicia[[787]]. When Rome began to absorb these provinces, slaves, prisoners, and merchants from them would naturally find their way to Rome, and in time would no doubt draw together for the worship of their national deities in the way that we have seen pursued by the worshippers of the Alexandrian Isis and the Jewish exiles. The magi of Asia Minor were great supporters of Mithridates, and the Mithridatic wars were no doubt responsible for a large number of these immigrants.
Once introduced, however, the worship of Mithras spread like wild-fire. The legions from the first took kindly to it, and this is the less surprising when we find that many of them were recruited under the earliest emperors in Anatolian states like Commagene, where the cult was, if not indigenous, yet of very early growth[[788]]. Moreover the wars of the Romans against the Persians kept them constantly in the border provinces of the two empires, where the native populations not infrequently changed masters. The enemy’s town that the legions besieged one year might therefore give them a friendly reception the next; and there was thus abundant opportunity for the acquaintance of both sides with each others’ customs. When the Roman troops marched back to Europe, as was constantly the case during the civil wars which broke out on the downfall of the Julian house, they took back with them the worship of the new god whom they had adopted, and he thus became known through almost the whole of the Roman Empire[[789]]. “From the shores of the Euxine to the north of Brittany and to the fringe of the Sahara[[790]],” as M. Cumont says, its monuments abound, and, he might have added, they have been met with also in the Egyptian Delta, in Babylon, and on the northern frontiers of India. In our own barbarous country we have found them not only in London and York, but as far west as Gloucester and Chester and as far north as Carlisle and Newcastle[[791]]. The Balkan countries, like Italy, Germany, Southern France, and Spain, are full of them; but there was one part of the Roman Empire into which they did not penetrate freely. This was Greece, where the memories of the Persian Wars long survived the independence of the country, and where the descendants of those who fought at Salamis, Marathon, and Thermopylae would have nothing to do with a god coming from the invaders’ fatherland. It is only very lately that the remains of Mithras-worship have been discovered at the Piraeus and at Patras, in circumstances which show pretty clearly that it was there practised only by foreigners[[792]].
Notwithstanding this popularity, it is not easy to say exactly what god Mithras’ European worshippers considered him to be. If length of ancestry went for anything in such matters, he might indeed claim a greater antiquity than any deity of the later Roman Pantheon, with the single exception of the Alexandrian gods. Mithras was certainly worshipped in Vedic India, where his name of Mitra constantly occurs in the sacred texts as the “shining one,” meaning apparently the material sun[[793]]. He is there invoked in company with Varuna, generally considered the god of the sky, and therefore according to some, the prototype of the Greek Zeus and the Latin Jupiter[[794]]. His appearance in a similar connection in the sacred books of the Persians led the founders of the comparative study of religion to think that he must have been one of the primitive gods of their hypothetical Aryan race, and that his worship must go back to the imaginary time when Persians and Hindus dwelt side by side in the plains of Cashmere. But this theory is giving way before proof that the original home of the Indo-European race was Europe, and has been badly shaken by the discovery at Boghaz Keui of tablets showing that the gods Mithra and Varuna were gods of the Mitannians or Hittites[[795]] at some date earlier than 1500 B.C., and therefore long before the appearance of the Persians in history. If the worship of Mithras were not indigenous in Western Asia, it may therefore well have come there independently of the Persians[[796]].
There is no doubt, however, that the roots of Mithras-worship went very far down into the Persian religion. In the Yashts or hymns which are the earliest evidence of primitive Iranian beliefs, Mithra—to use the Avestic spelling of his name—frequently appears, not indeed as the material sun, but as the “genius of the heavenly light” which lightens the whole universe[[797]] and is the most beneficent among the powers of Nature. Mithras is not here, however, the Supreme Being, nor even the highest among the gods benevolent to man. This last place is occupied in the Zend Avesta by Ahura Mazda, “the omniscient lord,” who appears to be the Persian form of Varuna, the god of the sky whom we have seen associated with Mitra in the Vedas[[798]]. Nor is Mithras in the Zend Avesta one of the six Amshaspands, the deified abstractions or personified attributes of Ahura Mazda, who, in the later developments of the Persian religion, occupy towards him much the same position that the “Roots” of Simon Magus and the Aeons of the Pleroma among the Gnostics do towards the Boundless Power or the Ineffable Bythos[[799]]. In the later Avestic literature, he appears as the chief of the Izeds or Yazatas, a race of genii created by Ahura Mazda, who are the protectors of his universe and the helpers of mankind in their warfare against the powers of darkness[[800]]. In the latest as in the earliest Persian view of the personality of Mithras, therefore, it is plain that he occupies an intermediate position between the Creator and man.
It is not, however, in the religion associated with the name of Zoroaster that we must look for the origin of Mithraism. The date of the sacred books of Mazdeism and the historical existence of Zoroaster himself have recently been brought down to as late as the VIIth century B.C.[[801]] and the appearance in Asia of the Persian tribes as conquerors, whereas Mithras was, as we have seen, worshipped in Asia Minor nearly a millennium earlier. Moreover, the strict dualism which set Ahriman, the god of darkness and evil, in eternal and perhaps equal opposition to Ormuzd, the god of light and goodness, seems to have been unknown before the Sassanid reform in 226 A.D., by which time the worship of Mithras in Europe was at its apogee[[802]]. M. Cumont is, therefore, doubtless right when he thinks that Mithraism was derived not from Mazdeism, but from Magism or the religion of the Magi, the tribe of Medes whose domination was put an end to by Darius the son of Hystaspes, and whose name was afterwards given to a priestly caste and has passed into our own language as the root of the word “magic.”
That these Magi practised a religion different from that taught in the Avestic literature is plain enough. The romantic story told by Herodotus of the Magian who seized the throne of Persia during Cambyses’ absence in Egypt on the pretence that he was the king’s brother whom Cambyses had privily put to death[[803]], is fully confirmed by Darius’ trilingual inscription on the Rock of Behistun, first copied and deciphered by Sir Henry Rawlinson and lately published in elaborate form by the British Museum[[804]]. Darius here narrates how “a certain man, a Magian, Gaumata by name ... lied unto the people (saying) ‘I am Smerdis, the son of Cyrus, the brother of Cambyses.’ Then all the people revolted from Cambyses and went over to him, even Persia and Media and the other provinces.” Darius goes on to record that “thereupon Cambyses died by his own hand[[805]],” that the seven Persian nobles overthrew the pretender much in the way described by Herodotus, and that “I rebuilt the temples of the gods, which that Gaumata, the Magian, had destroyed. I restored that which had been taken away as it was in the days of old[[806]].” This he tells us he did “by the grace of Ahura Mazda,” and that by this grace he always acted. The memory of these events was kept up by the festival of the Magophonia or Massacre of the Magi which was yearly celebrated in Persia and during which no Magus dared show himself in the streets[[807]]. Darius’ words show that there was a religious as well as a dynastic side to the Magian revolt, though whether the false Smerdis restored the old worship of the land, which he found in danger of being supplanted by Zoroastrianism or the worship of Ahura Mazda, may still be doubtful. In any event, the reformation or counter-reformation made by Darius did not succeed in entirely uprooting the old Magian faith, for Herodotus speaks of the Magi as still being in his time the priestly caste among the Persians, and as acting as diviners and sacrificers to the Achaemenian kings who ruled Persia up to Alexander’s Conquest[[808]].
The Magian religion as it appears in Herodotus and other Greek authors, however, seems to have shown none of the hostility to the powers of darkness so apparent in the religious literature collected by the Sassanian kings. “The whole circuit of the firmament” was, according to Herodotus, their greatest god or Zeus; and he says that they also “sacrifice to the sun and moon, to the earth, to fire and water, and to the winds”; but that “they do not, like the Greeks, believe the gods to have the same nature as men[[809]].” He also tells us that later they borrowed from the Arabians and the Assyrians the worship of a goddess whom he calls Mitra, and although he is probably wrong as to the origin and sex of this deity, his evidence shows that Semitic admixture counted for something in the Magian worship. In other respects, the Magian seems to have been a primitive faith given up to the worship of the powers of nature or elements, which it did not personify in the anthropomorphic manner of either the Semites or the Greeks, and to have paid little attention to public ceremonies or ritual. It follows therefore that, like the religions of many uncivilized people of the present day, it would draw no very sharp distinction between good and evil gods, and would be as ready to propitiate or make use of the evil, that is those hostile to man, as the good or benevolent. Plutarch, who describes the religion of the Magi more than three centuries after Herodotus, when the name of Zoroaster the Persian prophet and the dualistic belief favoured by his teaching had long been popularly known in the West, says that the Magi of his time held Mithras to be the “Mediator” or intermediary between “Oromazes” or Light on the one hand, and “Areimanios” or Darkness and Ignorance on the other, and that they used to make bloody sacrifices to the last-named in a place where the sun never comes[[810]]. It is easy to see how such a cult, without the control of public ceremonies and with its unabashed traffic with the powers of evil, would be likely to degenerate into compulsion or magic.
There was, however, another popular superstition or belief which, about the time when Mithraism made its appearance in Europe, had spread itself over Western Asia. This was the idea that the positions and changes of the heavenly bodies exercise an influence over the affairs of the world and the lot both of kingdoms and individual men. It probably began in Babylonia, where the inhabitants had from Sumerian times shown themselves great observers of the stars, and had been accustomed to record the omens that they drew from their motions for the guidance of the kings[[811]]. This kind of divination—or astrology to call it by a familiar name—received a great impulse after Alexander’s Conquest, in the first place from the break up of the Euphratean priestly colleges before referred to, and the driving out of the lesser priests therein to get their own living, and then from the fact that the scientific enquiry and mathematical genius of the Greeks had made the calculation of the positions of the heavenly bodies at any given date and hour a fairly simple matter to be determined without direct observation[[812]]. It was probably no mere coincidence that the Chaldaei and the Mathematici, as the astrologers called themselves, should have swarmed at Rome under just those emperors in whose reigns Mithraism began to push itself to the front[[813]].