Mithraism , also known as the Mithraic mysteries , was a Roman mystery religion centered on the god Mithras. The religion was inspired by Iranian worship of the Zoroastrian god Mithra , though the Greek Mithras was linked to a new and distinctive imagery, and the level of continuity between Persian and Greco-Roman practice is debated.
Worshippers of Mithras had a complex system of seven grades of initiation and communal ritual meals. Initiates called themselves syndexioi , those "united by the handshake". The cult appears to have had its centre in Rome ,  and was popular throughout the western half of the empire , as far south as Roman Africa and Numidia , as far north as Roman Britain ,  and to a lesser extent in Roman Syria in the east.
Mithraism is viewed as a rival of early Christianity. Numerous archaeological finds, including meeting places, monuments and artifacts, have contributed to modern knowledge about Mithraism throughout the Roman Empire. About sites have yielded materials related to the cult. Among the items found are about inscriptions, examples of the bull-killing scene tauroctony , and about other monuments.
Interpretation of the physical evidence remains problematic and contested. The term "Mithraism" is a modern convention. Writers of the Roman era referred to it by phrases such as "Mithraic mysteries", "mysteries of Mithras" or "mysteries of the Persians".
The exact form of a Latin or classical Greek word varies due to the grammatical process of declension. There is archaeological evidence that in Latin worshippers wrote the nominative form of the god's name as "Mithras". Modern historians have different conceptions about whether these names refer to the same god or not. John R. Mary Boyce , a researcher of ancient Iranian religions, writes that even though Roman Empire Mithraism seems to have had less Iranian content than historians used to think, nonetheless "as the name Mithras alone shows, this content was of some importance".
Much about the cult of Mithras is only known from reliefs and sculptures. There have been many attempts to interpret this material. Mithras-worship in the Roman Empire was characterized by images of the god slaughtering a bull. Other images of Mithras are found in the Roman temples, for instance Mithras banqueting with Sol, and depictions of the birth of Mithras from a rock.
But the image of bull-slaying tauroctony is always in the central niche. The practice of depicting the god slaying a bull seems to be specific to Roman Mithraism. According to David Ulansey, this is "perhaps the most important example" of evident difference between Iranian and Roman traditions: " In every mithraeum the centrepiece was a representation of Mithras killing a sacred bull, an act called the tauroctony.
The centre-piece is Mithras clothed in Anatolian costume and wearing a Phrygian cap ; who is kneeling on the exhausted  bull, holding it by the nostrils  with his left hand, and stabbing it with his right. As he does so, he looks over his shoulder towards the figure of Sol. A dog and a snake reach up towards the blood. A scorpion seizes the bull's genitals. A raven is flying around or is sitting on the bull. Three ears of wheat are seen coming out from the bull's tail, sometimes from the wound. The bull was often white. The god is sitting on the bull in an unnatural way with his right leg constraining the bull's hoof and the left leg is bent and resting on the bull's back or flank.
The event takes place in a cavern, into which Mithras has carried the bull, after having hunted it, ridden it and overwhelmed its strength. Outside the cavern, top left, is Sol the sun, with his flaming crown, often driving a quadriga.
A ray of light often reaches down to touch Mithras. At the top right is Luna , with her crescent moon, who may be depicted driving a biga.
In some depictions, the central tauroctony is framed by a series of subsidiary scenes to the left, top and right, illustrating events in the Mithras narrative; Mithras being born from the rock, the water miracle, the hunting and riding of the bull, meeting Sol who kneels to him, shaking hands with Sol and sharing a meal of bull-parts with him, and ascending to the heavens in a chariot.
On the back side was another, more elaborate feasting scene. This indicates that the bull killing scene was used in the first part of the celebration, then the relief was turned, and the second scene was used in the second part of the celebration. The second most important scene after the tauroctony in Mithraic art is the so-called banquet scene. Robert Turcan has argued that since the caduceus is an attribute of Mercury , and in mythology Mercury is depicted as a psychopomp , the eliciting of flames in this scene is referring to the dispatch of human souls and expressing the Mithraic doctrine on this matter.
Mithras is depicted as being born from a rock. He is shown as emerging from a rock, already in his youth, with a dagger in one hand and a torch in the other. He is nude, standing with his legs together, and is wearing a Phrygian cap. However, there are variations. Sometimes he is shown as coming out of the rock as a child, and in one instance he has a globe in one hand; sometimes a thunderbolt is seen. There are also depictions in which flames are shooting from the rock and also from Mithras' cap.
One statue had its base perforated so that it could serve as a fountain, and the base of another has the mask of the water god. Sometimes Mithras also has other weapons such as bows and arrows, and there are also animals such as dogs, serpents, dolphins , eagles, other birds, lion, crocodiles, lobsters and snails around. On some reliefs, there is a bearded figure identified as Oceanus , the water god, and on some there are the gods of the four winds. In these reliefs, the four elements could be invoked together. Sometimes Victoria, Luna , Sol and Saturn also seem to play a role.
Saturn in particular is often seen handing over the dagger to Mithras so that he can perform his mighty deeds. In some depictions, Cautes and Cautopates are also present; sometimes they are depicted as shepherds.
On some occasions, an amphora is seen, and a few instances show variations like an egg birth or a tree birth. Some interpretations show that the birth of Mithras was celebrated by lighting torches or candles. One of the most characteristic and poorly-understood features of the Mysteries is the naked lion-headed figure often found in Mithraic temples, named by the modern scholars with descriptive terms such as leontocephaline lion-headed or leontocephalus lion-head.
His body is a naked man's, entwined by a serpent or two serpents, like a caduceus , with the snake's head often resting on the lion's head. The lion's mouth is often open, giving a horrifying impression. He is usually represented as having four wings, two keys sometimes a single key , and a sceptre in his hand.
Sometimes the figure is standing on a globe inscribed with a diagonal cross. At the base of the statue are the hammer and tongs of Vulcan and Mercury's cock and wand caduceus. A rare variation of the same figure is also found with a human head and a lion's head emerging from its chest.
Although animal-headed figures are prevalent in contemporary Egyptian and Gnostic mythological representations, no exact parallel to the Mithraic leontocephaline figure has been found. Based on dedicatory inscriptions for altars, [b] the name of the figure is conjectured to be Arimanius , a Latinized form of the name Ahriman — a demonic figure in the Zoroastrian pantheon.
Some scholars identify the lion-man as Aion , or Zurvan , or Cronus , or Chronos , while others assert that it is a version of the Zoroastrian Ahriman or Vedic Aryaman. Jason Cooper, speculates to the contrary that the lion-headed figure is not a god, but rather represents the spiritual state achieved in Mithraism's "adept" level, the Leo lion degree.
According to M. Vermaseren and C. Mithraic initiates were required to swear an oath of secrecy and dedication,  and some grade rituals involved the recital of a catechism , wherein the initiate was asked a series of questions pertaining to the initiation symbolism and had to reply with specific answers.
An example of such a catechism, apparently pertaining to the Leo grade, was discovered in a fragmentary Egyptian papyrus P. Berolinensis ,   and reads:. Almost no Mithraic scripture or first-hand account of its highly secret rituals survives;  with the exception of the aforementioned oath and catechism, and the document known as the Mithras Liturgy , from 4th century Egypt, whose status as a Mithraist text has been questioned by scholars including Franz Cumont. Nevertheless, it is clear from the archaeology of numerous mithraea that most rituals were associated with feasting — as eating utensils and food residues are almost invariably found.
These tend to include both animal bones and also very large quantities of fruit residues. Mithraic feasts probably performed a very similar function for Mithraists as the collegia did for those entitled to join them; indeed, since qualification for Roman collegia tended to be restricted to particular families, localities or traditional trades, Mithraism may have functioned in part as providing clubs for the unclubbed.
Each mithraeum had several altars at the further end, underneath the representation of the tauroctony, and also commonly contained considerable numbers of subsidiary altars, both in the main mithraeum chamber and in the ante-chamber or narthex.
Burned residues of animal entrails are commonly found on the main altars indicating regular sacrificial use. However, mithraea do not commonly appear to have been provided with facilities for ritual slaughter of sacrificial animals a highly specialised function in Roman religion , and it may be presumed that a mithraeum would have made arrangements for this service to be provided for them in co-operation with the professional victimarius  of the civic cult. Prayers were addressed to the Sun three times a day, and Sunday was especially sacred.
It is doubtful whether Mithraism had a monolithic and internally consistent doctrine. In some mithraea, such as that at Dura Europos , wall paintings depict prophets carrying scrolls,  but no named Mithraic sages are known, nor does any reference give the title of any Mithraic scripture or teaching. It is known that intitates could transfer with their grades from one Mithraeum to another. Temples of Mithras are sunk below ground, windowless, and very distinctive.
In cities, the basement of an apartment block might be converted; elsewhere they might be excavated and vaulted over, or converted from a natural cave. For the most part, mithraea tend to be small, externally undistinguished, and cheaply constructed; the cult generally preferring to create a new centre rather than expand an existing one.
The mithraeum represented the cave to which Mithras carried and then killed the bull; and where stone vaulting could not be afforded, the effect would be imitated with lath and plaster. They are commonly located close to springs or streams; fresh water appears to have been required for some Mithraic rituals, and a basin is often incorporated into the structure.
The extant mithraea present us with actual physical remains of the architectural structures of the sacred spaces of the Mithraic cult. Mithraeum is a modern coinage and mithraists referred to their sacred structures as speleum or antrum cave , crypta underground hallway or corridor , fanum sacred or holy place , or even templum a temple or a sacred space. In their basic form, mithraea were entirely different from the temples and shrines of other cults.
In the standard pattern of Roman religious precincts, the temple building functioned as a house for the god, who was intended to be able to view, through the opened doors and columnar portico, sacrificial worship being offered on an altar set in an open courtyard—potentially accessible not only to initiates of the cult, but also to colitores or non-initiated worshippers.
There were seven grades of initiation into Mithraism, which are listed by St. A mosaic in the Mithraeum of Felicissimus, Ostia Antica depicts these grades, with symbolic emblems that are connected either to the grades or are symbols of the planets.
The grades also have an inscription beside them commending each grade into the protection of the different planetary gods. Elsewhere, as at Dura-Europos , Mithraic graffiti survive giving membership lists, in which initiates of a mithraeum are named with their Mithraic grades. At Virunum, the membership list or album sacratorum was maintained as an inscribed plaque, updated year by year as new members were initiated. By cross-referencing these lists it is possible to track some initiates from one mithraeum to another; and also speculatively to identify Mithraic initiates with persons on other contemporary lists such as military service rolls and lists of devotees of non-Mithraic religious sanctuaries.