Mithras is the normative Latin name of the central figure of a Roman mystery religion that is attested between the 1st-4th centuries.
Only very little is known of Roman Mithras' character, or of the beliefs and practices of his cult (the 'Mithraic Mysteries', from Latin Mysteria Mithrae). Although traces of his cult have been found all over the erstwhile Roman Empire, it is not sufficient for a thorough reconstruction of either Mithras or his cult. The earliest evidence of the Roman cult is from Rome itself and from the Roman provinces of Moesia Inferior (in the city of Novae), Germania Superior (Nida and Mogontiacum), Noricum (Ad Enum/Pons Aeni), Pannonia (Carnuntum), and Iudea (Caesaria maritima). These traces are all from about the same period, approximately 80-120 AD. The reason why the cult appeared more or less simultaneously at these great distances from one another is not known, but has been explained as being the work of a founder or group of founders whose writings are now lost. Whatever its beginnings, by about 300 the cult had spread all over the Roman Empire, with the highest density around Rome and Ostia, and along the Rhine and Danube frontiers. But the cult ended as quickly as it had begun; together with all the other so-called "pagan" religions of the Romans, the Mithraic Mysteries died out in the 4th century following the Roman emperor Constantine's imperial injunctions against all non-Christian beliefs and practices.
Despite the similarity of names, Roman Mithras should not be confused with Helleno-Zoroastrian Mithras, or with Zoroastrian (i.e. Greater Iranian) Mithra, or with Indian Mitra (of which there are two). Roman Mithras should also not be confused Manichaean Mihr, or with Armenian Myhr, or with Kushan Mirro. All these names are etymologically related, but they are all culturally independent figures. In the late 19th century and continuing up to the early 1970s, Roman Mithras was commonly assumed to have been a continuation of the Zoroastrian (i.e. Avestan, an Old Iranian language) divinity Mithra, and thus popularly identified as "the Roman form of Mazdaism". This theory is primarily due to the Belgian scholar Franz Cumont, whose works are now in the public domain and have been absorbed into popular imagination. In the Cumontian scenario, the cult was to have arrived in the Roman world via Mesopotamia and Anatolia, and during that journey, Mithras supposedly acquiring the characteristics that were alien to the Iranian world. However, since the first Mithraic Studies conference in 1972, the Cumontian hypothesis has been gradually abandoned, and although the name of the Roman god is generally acknowledged to have been borrowed from Avestan Mithra, Roman Mithras and his cult are now recognized to have been essentially products of Roman (and Greek-derived) thought. Whether the Romans borrowed much more than the name is difficult to establish from the meagre evidence. While the handful of borrowed words (like the names 'Mithras', 'Arimanius', 'Oromazdes') were once treated as arguments for continuity, these are now more easily explained to be superficial trappings of the Roman obsession with 'oriental wisdom'. In the case of the Mithraic Mysteries, this obsession with 'oriental wisdom' was represented by the Romans' belief that their cult and its practices had been founded by "Zoroaster", originally the name of an ancient Iranian prophet, but who in Roman and Greek understanding was primarily the "inventor" of astrology and magic. This utterly fanciful image of the Iranian prophet is the foundation of, and the reason for the cultic persophilia of the worshippers of Roman Mithras. That is, the adherents of the Roman cult, "who were manifestly not Persians in any ethnic sense, thought of themselves as cultic 'Persians.'" Functionally however, the Roman cult has nothing to do with the Iranian world, and it is doubtful whether an Iranian could have ever recognized the Roman cult as his own.
Like all other Mystery religions, and unlike the state-sponsored Greek-derived Roman religion, an adherent had to be inducted into the cult, and could not be born into it. The idea common to the various Mystery cults was that they claimed to possess certain occult and esoteric wisdoms ("mysteries", i.e. cult myths) that could only be revealed to these initiates, i.e. they were held secret from outsiders. This desire for secrecy was apparently especially effective in the case of the Mithraic Mysteries, since the writers of antiquity had little to report about them. The only exception is the report of Porphyry (On the Cave of the Nymphs 6), which is based on the testimony (now lost) of a certain Eubolus. This text is of immense importance to the modern understanding of the nature of the Mithraic mysteries, i.e. what the "mystery" (the cult myth) of the Mithraic mysteries was: the transition of a mortal to a god-like immortal, and back again. This transition was supposedly brought about by the worship of Mithras in a cave, the cave being the image of the "world cave" (i.e. the universe) and vice-versa. In this transition, Mithras was apparently a salvific agent, probably some sort of mediator between the divine world and the earthly world. Such beliefs of salvific transition were commonplace in the beliefs of the middle Platonic school, to which the Mithraic mysteries evidently belonged, and which was the reason for Porphyry's interest in them.
As far as the performance of religious practices are concerned, the Roman cult seems to have been limited to men. None of the hundreds of statuary dedications is from a person with a woman's name, and none of the dedications refers to family or female relatives. Although there have been many hypotheses that attempt to explain this unusual practice, none are conclusively established, and the reasons remain unknown. In the 19th century Cumontian scenario it was also assumed that the Roman cult had a special appeal to soldiers. This was because the vast majority of the dedicatory inscriptions were made by soldiers or ex-soldiers. Since the 1950s there has been a general drift away from this assumption. While it is true that the majority of the dedications are from persons with a military background, the statistic provides a different picture when the locations where the evidence was found is taken into consideration: the Roman presence was greatest in the frontier towns of the Roman empire, and because these towns were on the frontier they had a high percentage of soldiers. Accordingly, in towns where the density of soldiers was higher, the number of dedicatory inscriptions made by soldiers was higher. Inversely, in towns where the density of civilians was higher, the number of dedicatory inscriptions made by civilians was higher. This is particularly evident in Rome, Ostia and other trading centers; in these cases the civilian inscriptions far outnumber the military ones.
All Roman religions, including the Mithraic Mysteries, were non-exclusive. That is, noone belonged exclusively to a one cult alone. Rather, the Roman attitude to religion was intensely pragmatic; in the belief that what was good for others could also be good for oneself, almost everyone belonged to multiple cults. This was also the case for the Mithraic Mysteries, and Mithraic temples are replete with references and dedications to other Roman gods. The Mithraic mysteries was in essence an astrological cult, and accordingly the most common are the other Roman gods that appear in Mithraic iconography are those associated with astronomical bodies: the Sun (Sol/Helios) and the Moon (Luna/Selene) which appear on numerous Mithraic altar pieces. Not as commonly, but still frequent, are the appearances of Mercury, Venus, Mars, various Jupiters, Uranus, and Saturn. Non-astrological Roman figures that often appear in Mithraic contexts are Oceanus, Tellus, and Juno. Besides Mithras, two other names originally from Zoroastrianism also appear: Arimanius (via Middle Iranian Ahriman from Avestan Angra Mainyu) appears four times, and Oromasdes (via Middle Iranian Ormazd from Avestan Ahura Mazda) appears once. As is also the case for Mithras, there is not enough evidence from which to infer the characteristics of the figures behind the adopted names (that Arimanius is a deus in the Mithraic inscriptions should not be construed to imply that Arimanius was a god in the modern sense. In Roman religion every supernatural entity -- both good and evil -- is a deus).
One of the more popular myths in modern imagination is one that fancies that the Mithraic mysteries was a particularly important cult. It was not. By far the greatest number of Roman religion-related archaeological remains are those of the various cults of the state-sponsored classical Roman religion (i.e. Jupiter and so on), and of the Roman imperial cults. The traces of all the various Mystery cults together represent just a fraction of all Roman religion-related finds, and even among these the evidence from the Mithraic mysteries is only moderately common. Even if there were twice as many Mithraic temples as have so far been rediscovered (about 200), and all of them were in use at the same time (which they were not), the shrines were so small (intentionally so) that on average at most 10-15 people could have fitted in each one. The total number of worshippers at any one time would then have only been about 5000 people, which is less than 0.1% of even the most cautious estimates of the population of the mid-2nd century Roman empire (65 million).
One of the reasons why the Mithraic mysteries is mistakenly assumed to have been important is the early/mid-19th century confusion of Mithras with Sol Invictus, who is a different Roman god. Although Mithras does carry the epithet "Sol Invictus" (meaning "invincible sun") in many 3rd and 4th century inscriptions, the god Sol Invictus is a figure in his own right, a figure of classical Roman religion, with whom many other gods (including Mithras) were associated. There is no reason whatsoever to identify Sol Invictus as Mithras; in Mithraic art they are two distinct figures. Also contributing to the error is a mid-19th century remark by Ernest Renan, in which the French philosopher supposed that the world would have been Mithraic if Christianity had not prevailed. This gross exaggeration excited the public fancy, which henceforth began to attribute all sorts of "borrowings" in Christianity to the Mithraic Mysteries. Among the most commonplace is the notion that Christmas was originally a Mithraic festival of Mithras. But there is no evidence whatsoever for any kind of festival of Mithras, leave alone a public one that supposedly occurred at the end of December. The origin of the idea that Mithras might have something to do with the Winter Solstice (21 December in the modern Gregorian calendar, 25 December in the Roman calendar) likewise derives from the confusion with Sol Invictus; it is Sol Invictus, not Mithras, whose public festival was celebrated on 25 December. Numerous other attributes of Christianity are similarly assigned to the Mithraic Mysteries, but all of which are either not properties of it (e.g. the aforementioned December 25th myth, or the Taurobolium, which is actually of the Magna Marta cult and is not related to the Mithraic Tauroctony), or are part of the general religio-cultural fabric of the Roman empire and which thus cannot be assigned specifically to the Mithraic Mysteries. The contrary notion that the mysteries borrowed from Christianity is equally inaccurate when it ignores that all Roman religions -- which includes early Christianity -- borrowed from one another. It was only with the (comparatively late) arrival of Christian missionary anti-pagan polemics that the situation began to change.
- Roger Beck (1984), "Mithraism since Franz Cumont," Aufstieg und Niedergang der romischen Welt (ANRW) II.17.4, pp. 2002-2115.
- Roger Beck (2004), Beck on Mithraism: Collected Works With New Essays, London: Ashgate.
- Ugo Bianchi, ed. (1979), Mysteria Mithrae, Leiden: Brill.
- Manfred Clauss (2000), The Roman Cult of Mithras: The God and his Mysteries, New York: Routledge.
- Manfred Clauss (1992), Cultores Mithrae, Stuttgart: Franz Steiner.
- Jacques Duchesne-Guillemin, ed. (1978), Études Mithriaques, Leiden: Brill.
- Richard Gordon (1996), Image and Value in the Graeco-Roman World, studies in Mithraism and religious art, London: Variorum.
- John Hinnells, ed. (1975), Mithraic Studies, Manchester University Press.
- Reinhold Merkelbach (1984), Mithras, Königstein: Hain