Foreign religions grew rapidly in the 1st-century A.D. Roman Empire, including worship of Jesus Christ, the Egyptian goddess Isis, and an eastern sun god, Mithras

A colorful fresco of the Mithraeum at Marino, Italy, shows the god Mithras slaying a bull. This scene is known as the tauroctony. (Wikimedia Commons)

Of the religions that expanded rapidly in the 1st-century Roman Empire, worship of Mithras was particularly popular among Roman soldiers, who spread his cult during their far-flung travels. But no written evidence from the Mithraists themselves survives, and the literary evidence we have is mostly by Christian detractors. Mithras's temples, called Mithraea, are the best archaeological evidence of the god's worship, and most of them featured a characteristic depiction of Mithras slaying a bull, a scene called the tauroctony. Sifting through this imperfect record, scholars have been able to conjecture about many aspects of this once widely practiced religion.

Greco-Roman religious scholar Luther Martin says that Mithraism remained de-centralized throughout the Empire. Its contemporary, Christianity, got its central administration from St. Paul, who derived it from Judaism. Both it and Mithraism "were...pretty much locally controlled affairs," he says, though Christian communities did "come together as a coherent institution...after Constantine."

In later years, Christian commentators recognized similarities between Mithraic and Christian rites and were quick to condemn them. In Chapter 70 of Dialogue with Trypho, the 2nd-century Christian author Justin Martyr writes that Mithras's worship in a cave and his "rock birth"--a frequent depiction of the god, emerging from a stone--is taken from Daniel 2:34 and Isaiah 33. The Mithraists "have no understanding" of these Scriptures, says Justin.

Mithras shown born from a rock (petra genetrix in Latin) (Wikimedia Commons)

Justin Martyr LXXI: "And when those who record the mysteries of Mithras say that he was begotten of a rock, and call the place where those who believe in him are initiated a cave, do I not perceive here that the utterance of Daniel, that a stone without hands was cut out of a great mountain, has been imitated by them, and that they have attempted likewise to imitate the whole of Isaiah's words?"

Daniel 2:34: "While you were watching, a rock was cut out, but not by human hands. It struck the statue on its feet of iron and clay and smashed them."

In Chapter 66 of First Apology, Justin claims that "wicked devils...imitated" the Eucharist by creating a Mithraic communal meal. In Chapter 40 of The Prescription Against Heretics, the 2nd-century Christian writer Tertullian notes that Mithraists "celebrate also the oblation of bread and introduce an image of a resurrection." Aside from Tertullian, however, no other ancient source scholar mentions the image of resurrection in Mithraic ritual.

Jesus was not the only deity with whom Mithras shared similarities. In the later Roman Empire, Mithras blended in with another sun god, Sol Invictus, the "unconquered sun." Both gods appeared in the Spanish provinces around the same time, according to Jaime Alvar, an ancient history professor at the Universidad Carlos III de Madrid. Some 1st-century votive offerings in Rome even conflate the two gods into one deity, "Sol Invictus Mithras."

Sol Invictus (with a halo of sunlight) and Mithras (to his right) feast together. (Wikimedia Commons)

By the 5th century, Mithraism faded. However, Mithras and Sol Invictus have echoes in the worship of Jesus Christ. Martin believes the ideas of brotherhood in Mithraism and apostleship in Christianity descend from collegia, or Greek social and political clubs. "My own take is that you've got two religions developing at the same time and in the same place and in the same culture and they're going to develop similar kinds of expressions, symbolic expressions," he adds.

The Origins of Mithraism

The first mentions of "Mitra" come from India and Iran. The Rig Veda is a collection of sacred Sanskrit texts composed as early as 1200 B.C. Its Hymn 66 invokes "Mitra," a protector of the law and a god of light. In Iran, Mithras continued in the same vein: the modern Farsi word for "sun" is "mehr," also the root of "Mithras." The Greek historiographer Strabo (63 B.C.-A.D. 23) corroborates this report in Book XV of his Geography, noting that the Iranians "worship the sun also, whom they call Mithras." In Hymn 10 of the Yasht, an Iranian collection of praise poems to gods dating from after 250 B.C., Ahura Mazda, the god of light, commends Mithras. He tells his disciple, Zoroaster, that Mithras respects justice and brings "down terror upon the bodies of the men who lie...to [him]."

"We pretty much know for certain he wasn't originally a sun god," says David H. Sick, chair of the Greek and Roman Studies department at Rhodes College, who uses extant literary sources to study the Iranian Mithras. He adds, "The original meaning of the god's name is 'contract', so he starts with 'contract' and, somehow, becomes the solar god. ...The reason that the contract god may become a solar god is because both contracts and the sun are related to sacrifice."

In Roman reliefs, Mithras kills a bull, an action called a tauroctony. In Indo-Iranian myths, men sacrifice cattle to please the gods. Sacrifice is an element of proper conduct in Greek mythology, which Sick argues was heavily influenced by Indo-Iranian stories. If one does not sacrifice to the gods and fulfill his part of the human-divine contract, that individual will be punished. The all-seeing sun witnesses contracts between the divine and mortal worlds and also is the master of cattle-for example, Helios's herds in Book XI of Homer's Odyssey. Though Sick maintains these cows are distinct from the bull of the tauroctony, he places great emphasis on the mythological connections that produced the Iranian Mithras and his Roman cousin.

The tauroctony scene, in which Mithras kills the bull, from Rome (Wikimedia Commons)

The 19th-century Belgian archaeologist Franz Cumont, considered the father of Mithraic studies, believed that Roman Mithras was a direct descendant of the Iranian Ahura Mazda, but modern scholars now believe Mithraism was a separate development. "There's Persian elements there [in Roman Mithraism], but where they appear in Mithraism is not the way they appear anywhere in Persian materials," says Luther Martin. Roman Mithras was a distant relative, not a direct descendant, of Indo-Iranian gods.

If Mithras was a Roman creation, why did he retain the Iranian influences, like his name and solar association? "Again, we're speculating, but the Romans, like modern Americans, were fascinated by the wisdom of the east," says Martin. The Romans had an attitude of mixed veneration and condescension for eastern knowledge, says Roger Beck, author of several books on Mithraism. Though it had conquered the east, the Greco-Roman world still saw "these civilizations [as] older and thus [having] access, particularly in physiologies, to speculation about the gods and maybe secret" knowledge, Beck says. To access these ancient secrets, perhaps the Romans mimicked eastern rites and gods.

Roman Religion Wasn't Built in a Day

Mithraism made its way west in the Roman Republic's late years. In his Life of Pompey, the historian Plutarch recorded that pirates from Cilicia, in southern Turkey, brought Mithraic rites to Rome in the 1st century B.C. In Asia Minor, Mithras was an important god, as seen in the name of Mithridates VI, king of Pontus in northeastern Turkey. Mithridates, whose name means "gift of Mithras," opposed Rome in a series of three wars, only to be defeated by Pompey the Great in 63 B.C.

In Mysteries of Mithra (1903), Franz Cumont wrote that this relief represented the Commagenian king Antiochus I and Mithras. (Wikimedia Commons)

Beck believes that the cult evolved from the kingdom of Commagene in southeastern Turkey. In the 1st century B.C., he says, the Greco-Persian ruling dynasty of Commagene worshiped Mithras as a sun god. He also argues that Mithraic symbols from Commagene can be interpreted in an astrological light. Commagene's royal family was well versed in astrology: the famous Roman astrologer Balbillus married into the clan.

The first Roman inscription mentioning Mithras dates from the 1st century A.D., when a slave of one of the emperor Trajan's administrators dedicated a sculpture to the god. Around the same time, in what is now Frankfurt am Main in Germany, soldiers began to build temples to Mithras, called Mithraea.

What caused the growth of Roman Mithraism? As Rome's empire expanded in the first and second centuries A.D., new gods traveled with immigrants and soldiers. The first century brought an influx of international trade under Emperor Augustus's "Pax Romana," or "Roman Peace." The movement of goods parallels the movement of religions about the Roman world at this time. From Italy, Mithraism spread outward to the provinces as soldiers traveled to imperial provinces. They brought their god with them and established temples.

A bull-killing god appealed to warriors. "The tauroctony would appear, I argue, to most Romans as a sacrifice. Sacrifice has to do with blood, so you get the blood imagery, which the soldiers are involved in," says Martin. In Mithraic rites, "one could see the value of bonding, of brotherhood, of hunting, of sacrifice, of blood, of the kinds of patterns you will in counter in militaries throughout the world." In a wall painting at the Mithraeum in Dura-Europos, Syria, Mithras is depicted as a hunter on horseback. Here, he fights in the same manner as the some of the local Roman legionnaires--archers from the Syrian city of Palmyra. Such scenes show that the soldiers thought of Mithras as one of their own.

Mithras appears as a Palmyran archer in the Mithraeum from Dura-Europos. (Carly Silver at the Yale University Art Gallery)

In contrast to Greco-Roman gods like Jupiter and Apollo, Mithras was not a state-sponsored deity. He was worshiped in a private community with secret rituals. "It is a completely de-centralized religion," says Martin. "This is interesting because they're [the Mithraea] all completely recognizable, so there was some sort of communication that's going on." Unlike the aristocratic Roman high priests, Mithras's followers came from all walks of life, Beck adds. "There is no suggestion" that only an "eternal, esoteric Mithraic elect" could experience spiritual rejuvenation, he says. "As far as we know, the initiation...was open to all," except women. However, evidence from North Africa suggests that some Mithraic rites may have included females.

Few public documents remain to recount the cult's rituals. "It seems as though these groups didn't produce any texts," says Martin. Surviving literary evidence comes from later periods. "Even in the Roman side of things, the literary sources we have about Mithraism are from non-Mithraists because Mithraism was a mystery cult," says Sick. "Mithraists, the ones that respected the cult, wouldn't tell what they were doing and so a lot of what you get are from later Christian apologists, who are attacking the religion."

Mithraic Rituals

An initiate had to pass a series of tests to enter the cult, after which he was ceremonially "reborn" and accepted by the group's leader, or Father (pater in Latin). The Father represented Mithras's authority on earth. In his Letter to Laeta from A.D. 403, St. Jerome lists the seven rankings of a Mithraic initiate in ascending order: raven (corax), bridegroom (nymphus), soldier (miles), lion (leo), Persian (Perses), sun-runner (heliodromos), and Father.

A depiction of the tools of a pater, a grade of Mithraic initiation; his tools include Mithras's characteristic Phrygian cap (Wikimedia Commons)

Each rank may be associated with a planetary counterpart, though sketchy details survive about individual ranks. Those who reached "lion" level offered incense to Mithras and bathed in honey, according to the 3rd-century A.D. philosopher Porphyry. The 4th-century writer Ambrosiaster claimed that initiates were blindfolded and had to make the animal sound corresponding to their desired rank.

The initiation rituals "involved techniques that produced altered states of consciousness," says Martin. "They were held at night or in darkness with flickering candles and weird masks. These things would be life-threatening, at least in the metaphorical sense." He believes images on artifacts like an "initiating father aiming a bow and arrow at an initiate's head, close-up" represent actual initiation rites. These rituals would be "presenting threats under conditions that might produce altered states of consciousness...and these things become pretty memorable."

These rituals re-created stories about Mithras. One tale found Mithras striking a rock with an arrow to produce water in a dry place, making him a "civilizing force." "The story was presumably about one of the heroic feats performed by Mithras," Beck says. The story of the bow-wielding Mithras "comes out of the tradition of Persian [and] Parthian archery. Archery is what heroic figures from the East do," notes Beck, "[and] it then makes sense that...he, Mithras, uses a bow and arrow in the stories for civilizing purposes."

In the initiation, a pater would aim a bow at an individual, Beck says, to "scare the bejeesus out of" him. Beck references a cup found in Mainz, Germany, showing this scene. Mainz "was the headquarters for two kinds of legions," he says. "These were very tough guys, who knew about handling weapons." In order to create a memorable initiation experience, "this initiate would be brought in and the first thing he sees is this very senior figure with a taut bow and arrow ready to fly right at him," Beck adds. "Many initiations work through terror."

Through an Ancient Lens

How did the ancients understand Mithraic imagery? "Nobody in antiquity gives an explication, explains what the function is--if there was one--of the bull-killing relief," says Beck. Because no explanations or texts written by Mithraists survive, Martin suggests that initiates conveyed meaning through the images. Mithraea were shaped like caves. In On the Cave of the Nymphs, the 3rd-century A.D. philosopher Porphyry noted, "Wherever Mithra[s] was known, they propitiated the god in a cavern," he wrote. Mithras killed the bull in a cave; Porphyry also wrote that the first Mithraeum was a cave in Persia.

In his work, Sick notes the association of caves and solar imagery in Indo-Iranian mythology, citing an Indian myth of "the creation of a sun from a cave." Experts do not agree on which constellation the tauroctony represents: some argue for Perseus, while others support Orion. To Cumont, the tauroctony showed Mithras's power over the most precious of resources. In The Mysteries of Mithra (1903), Cumont says that, for the ancients, "cattle [was] the source of all wealth." When Mithras captured and killed the bull, that deed would be a mark of honor.

Many modern scholars lend credence to an astronomical interpretation of the Mithraeum. "The whole Mithraeum is set up as a miniature cosmos," Martin says. "You always get images of Mithras's cloak as the stars or planets. The astrological-astronomical basis of Mithraic imagery is fairly clear." Beck interprets the cave as "an image of the universe" in miniature. "Its function has to do somehow with the descent of the soul into mortality and the ascent out again of the soul into mortality," he says.

Astronomical signs were a means to understand Mithraic iconography, Beck says; he calls this language "star talk." "I think that's finally what it is, the language-like thing. It's a tool, a medium, through which you express yourself, through which you make representations." Because the ancients left no instructions on how to interpret this "star talk," Beck admits there is no way to understand the symbols' meaning. "When you play in the astronomical-astrological factors, the danger of scholarship is the danger of trying to decode," Beck says.

Based on literary evidence, Sick argues for additional interpretations. "The astrological material...might appeal to a certain type of devotee, but it has to be one, I think, that's fairly well-educated to understand what's going on there. I think it would be an elite member of the cult that would have that interpretation." Sick notes that common soldier-devotees of Mithras would not be educated enough to understand star talk. "There has to be, in my view, another series of stories, myths, phenomena that can be understood much more simply" to explain the rites.

The standard structure of a Mithraeum is a long hall with benches on either side, with a depiction of the tauroctony at the end. (Ken Pennington)

Early Archaeology of Mithraism

In the 19th century, several major finds resurrected interest in Mithraism, especially in Rome and its nearby port, Ostia. In the 20th century, Franz Cumont uncovered the Mithraeum of Dura-Europos and published his research in a series of books, including The Mysteries of Mithra. The standard form of a Mithraeum was a long room with benches on either side, culminating in a cult niche, where a tauroctony and votive offerings would be found.

The tauroctony in the Mithraeum beneath the Basilica di San Clemente, Rome (Claudia Porcel)

Rome boasts some of the world's most famous Mithraea. Between A.D. 212 and 217, the Roman emperor Caracalla built a massive bath complex. In 1908, archaeologists began to excavate beneath these baths, and, four years later, they discovered the largest Mithraeum found to date in Rome. Few carvings survived from this Mithraeum, but a marble fragment of a relief found shows Sol, the Roman personification of the sun, and Luna, or the moon. A smaller inscription gives Mithras the epithet of "unconquered," further associating Mithras with Sol Invictus. Other reliefs appear to have been deliberately destroyed; only pieces of the tauroctony survived.

Perhaps the most famous Roman Mithraeum is underneath the Basilica di San Clemente. First excavated in 1914, this Mithraeum is similarly shaped to that in the Baths of Caracalla: a long, rectangular room with benches on either side, culminating in a cult niche. The arched roof of the San Clemente temple is remarkable for its implications on Mithraic theory. It contains 11 holes, four of which scholar W. Marburg Lentz identified as ventilators. The other seven may represent seven celestial bodies. This possible identification has led some scholars to theorize that Mithraic iconography had ties to star maps and equinoxes.

With ships coming in from all over the world, Rome's port of Ostia was subject to many foreign influences. It is no wonder, then, that more than a dozen Mithraea have been identified there. The Mithraeum of the Seven Gates was built around A.D. 160-170. A plaster-topped altar stands near mosaics depicting Mithraic symbols. Most striking, though, is the floor mosaic, showing a center archway framed on each side by three more arches. These "seven gates" give this Mithraeum its epithet. The recurrence of the number seven resonates with St. Jerome's description of seven ranks of Mithraic initiation. This gate mosaic is located behind the entrance to the Mithraeum: once one has stepped into the temple, the initiation has begun.

The Mithraeum at Dura-Europos in eastern Syria was a spectacular find, discovered in 1934. It came to international prominence through the likes of Cumont and seems to be contemporaneous with the Ostian Mithraeum of the Seven Gates. The first local inscription--accompanied by a tauroctony--dedicated to Mithras dates from A.D. 168, around when Rome occupied Syria. In one wall painting at Dura, Mithras is depicted as a Palmyran archer, a hunter with bow and arrow. Many of the Roman soldiers stationed at Dura were archers from nearby Palmyra.

The remains of the Mithraeum at Walbrook, London (Andrew Taylor)	A dedicatory relief to Mithras from the soldier Ulpius Silvanus from the Walbrook Mithraeum in London (Museum of London)

Mithras also held sway in Britain. In 1954, W. F. Grimes found a Mithraeum in Walbrook, London. Dating from the mid-2nd century, this temple contained a white marble head and bust of Mithras. Inside, a tauroctony was found with a dedication from a Second Legion soldier named Ulpius Silvanus that may have been originally located with other votive offerings in the cult niche.

Recent Discoveries

In the past 15 years, Mithraea have been unearthed everywhere from Spain to Iraq. Many of them boast similar construction, consisting of a rectangular room with a place for votive offerings at its end. The temples were often constructed during Mithraism's heyday of the 2nd and 3rd centuries A.D.

April 2010: After decades of controversy, a long-closed sanctuary of Mithras was finally reopened. This Mithraeum is located in the Rhodope Mountains in the town of Thermes on the border between Greece and Bulgaria. Because of the tensions between Communist Bulgaria and Greece in the 20th century, the site's excavator, Bulgarian archaeologist--and eventual prime minister--Bogdan Filov, conducted no further enquiries into the site after his initial foray in 1915. So far, the findings merely consist of a sacred spring and a sculptured relief. Bulgarian officials have called for increased Greek involvement in a further investigation, which will lead to a planned tourist venture in the area. Interestingly, Bulgarian archaeologist Nikolay Ovcharov identified the veneration of rocks as a cultic ritual that was part of this Mithraic complex, resonating with the story of Mithras's rock birth.

April 2010: Archaeologists discovered the remains of a Mithraeum in Angers, northwestern France. First constructed in the 3rd century A.D., the temple is located inside a domus, or Roman house. The temple was probably destroyed in the 4th century, as evidenced by shattered statues and signs of burning. It contains remains of a relief depicting Mithras with torchbearers and of a worn head of the god, distinguished by his Phrygian cap. The offerings included about 200 coins. Other artifacts found include Nubian terracotta figurines, a brooch, and a deer-shaped pouring device with three holes in its throat, perhaps used in an unknown rite. Unfortunately, because the area is due to be razed for housing, archaeologists may not have much more time to excavate.

2009: A Mithraeum was found in Iraq in the northern province of Dohuk. The prayer space in this Mithraeum faces the sun, says Hassan Ahmed Qassim, Dohuk's director of antiquities. Such a location seems apt, considering Mithras was a solar deity. Qassim says that the Mithraeum's discovery is important in understanding the historical transformation of the region. While this area was never under official Roman rule, Dohuk may have come under its influence.

2009: An Italian farmer outside Rome discovered a giant marble relief of Mithras on his property. Dating from the 2nd century, the relief had been excavated illegally. Made of Tuscan marble, it originated in the Etruscan city of Veio, about 12.4 miles from Rome. At the time, Italian police believed thieves planned to smuggle it to Japan or China through the United Arab Emirates. Weighing more than 3,000 pounds, the relief was to be sold for 500,000 euros.

2008: A Mithraeum was discovered under a modern shopping mall in Szombathely in northwestern Hungary by archaeologist Peter Kiss. This temple is the first example for Mithraism in Szombathely, though evidence for the cult has appeared elsewhere in Hungary. Thus far, the excavated area consists of an outer room and an entranceway. The temple burned down in the 4th century, as evidenced by pieces of ceiling and wall paintings found on the floor. Currently, an artistic restorer is working to recreate the shattered paintings, which used expensive pigments in their construction.

Excavating the Mithraeum at Lugo, Spain (Jaime Alvar)	C. Victorius Victorinus's offering to Mithras from the Lugo Mithraeum (Jaime Alvar)

2003: A Mithraeum was discovered in Lugo, called "Lucus Augusti" in Roman times, in northwestern Spain. While examining a manor house, or pazo, in an area under consideration for building expansion, workers found the Mithraeum. As it turned out, the pazo was on top of an old Roman residence. Historian Jaime Alvar theorized that the temple's cult niche was destroyed during the Mithraeum's construction. The temple was most active in the 3rd and 4th centuries. A granite altar found was dedicated by one C. Victorius Victorinus, who calls himself a "centurion of the Seventh Legion" in the inscription. The inscription dubs Mithras "invictus," or "unconquered," allying him with Sol Invictus.

2000: Daniele Manacorda of Roma Tre University found another Mithraeum in Rome, located in the Crypta Balbi at the southern end of the Campus Martius. This Mithraeum was built in the early 3rd century and used until the late 4th century. The temple has the typical Mithraic structure, though the cult niche has not yet been found. A fragment of a third-century tauroctony was discovered.

Reconstructing the Mithraeum at the Crypta Balbi (Michael Tinkler)

1998: Archaeologists excavated a Mithraeum at Hawarti in Syria; initial forays were made into the building the 1970s, but not completed until the '90s. Underneath what was a Christian basilica in the 4th and 5th centuries A.D., the Mithraeum was revealed when the basilica floors collapsed. By dating date of coins, pottery, and lamps to the mid-4th century A.D., archaeologists have proposed that this Mithraeum is the latest constructed of those yet found. Roger Beck characterizes the iconography of the Hawarti wall paintings as "all over the place." He adds, "There are these strange, strange figure[s] of Mithras holding...naked, black demonic figures by chains." He suggests that this scene represents evil overcome by good, personified by Mithras.

1993: Construction workers were clearing an area in Martigny, southern Switzerland, for apartment buildings, when, to their surprise, they found a Mithraeum built between A.D. 150 and 200. A long room with benches on either side, this Mithraeum has a podium at the end for a tauroctony and other votive objects. Dedicatory offerings here ranged from coins to an earthenware vase bearing a Greek inscription from one Theodoros to the Greek sun god Helios. This offering reinforces the notions of Mithras's worship under various epithets.

Carly Silver is a junior at Barnard College, Columbia University, in New York City. A religion major, she is concentrating on ancient belief systems and their effects on the development of monotheism.

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