Persian Empire
Deep Dive 9 min read

Mithraism and the Cult of Mithras: From Iran to the Roman Empire

A mithraeum in the Bloomberg European HQ in the City of London, excavated in 2014, joined a list of about seven hundred known across the Roman Empire. The Bloomberg cult room, dedicated to Cautes and Cautopates in the standard iconography, was preserved because the site had been sealed under a later Roman pavement. The finds included a marble head of Mithras in his Phrygian cap, oil lamps, and a small pottery beaker. London is well north of where most Mithraea are found — the cult’s centre of gravity was along the Rhine, the Danube, and in Rome and Ostia — but the Bloomberg find is, I think, a useful reminder that the cult was widely distributed in the second through fourth centuries, and that the urban cellars of Roman Britain and Roman Germany have been the most productive source of new material in the last two decades. The other recent find of note is the Mithraeum of Hawarte in Syria, excavated by the Polish mission before the civil war, and the Mithraeum at Černý Most in Prague. Both have refined the picture without overturning it.

The English literature on the Roman cult is anchored by Manfred Clauss’s The Roman Cult of Mithras: A New Approach (2000; the English translation is by Richard Gordon). David Walsh’s The Cult of Mithras in Late Antiquity (2019) is the most recent synthesis of the archaeological side. Roger Beck’s The Religion of the Mithras Cult in the Greek and Latin Literature (2006) is the indispensable book on the texts. Richard Gordon’s “The Roman Empire and the Cult of Mithras” in A Companion to Roman Religion (2007) is the best short statement. For the Iranian side, Frantz Grenet’s work in the Encyclopaedia Iranica and his Mithra, iżwar und die anderen for the Iranian side, the working references. Gherardo Gnoli’s The Idea of Iran vol. III treats the Sasanian cult of Mithra in the imperial context.

For the connected clusters, see Zoroastrianism and Persian Mythology and Ahura Mazda. The long-tail page on the Yashts treats the Iranian material in more detail.

The Iranian god Mithra

Mithra is, in origin, an Indo-Iranian deity. The Vedic Mitra and the Avestan Miθra share a name and a function. The Rigvedic Mitra is the friend, paired with Varuna the cosmic orderer. The Avestan Miθra is one of the senior yazatas, and the Mihr Yasht (Yasht 10) is the longest of the Yashts in the standard editions, with about 140 verses. The “1,200 verses” sometimes cited in older works is wrong; the text is around 140 verses in the standard edition, and the inflated figure is a confusion.

The Mihr Yasht describes Mithra as a warrior who rides through the sky in a chariot drawn by white horses, watches the world from a high lookout (a hilltop, “where the two ends of the earth meet”), smites the daevas, and brings the water from the cosmic ocean to release on the earth. He is the yazata of contracts and of the lie: he watches over honest dealing and punishes the oath-breaker. Boyce’s History of Zoroastrianism vol. II (1982) gives the Iranian cult of Mithra in pre-Hellenistic form. The cult is a theologically important in the Avesta, and the figure of Mithra in the Yasht is a closer match to the Roman Mithras than the figure of Ahura Mazda is to any Roman deity.

The name Miθra appears in personal names of the western Iranian Magupat and in Achaemenid inscriptions. The land of the Magi attested in the Persepolis Fortification Tablets is a region in central Asia, and the Achaemenid cult of Mithra is documented in the inscriptions and in the archaeology of western Iran. Whether the Achaemenid cult fed directly into the Roman religion is one of the great unanswered questions of the field. Grenet has argued for a substantial Iranian contribution, with the Sasanian-era cult of Mithra in the Sasanian west as a transitional stage. Clauss, Beck, and Gordon are more sceptical; most modern scholars would now say the Roman cult was a Roman construction, drawing on Iranian iconography and the figure of Mithra as known through the Roman encounter with Cilician pirates, eastern merchants, and the legions stationed in the east.

The Sasanian cult

The Sasanian dynasty, from 224 CE, gave Mithra a central place in the imperial cult. The cydaris (the Greek form of the Sasanian taj, the royal diadem) was associated with the farr (the divine glory of kingship), and Mithra, as the yazata of the khvarenah (the royal glory) and of the rising sun, was the natural patron of a dynasty that claimed universal rule. The Sasanian rock reliefs at Naqsh-e Rostam, Bishapur, and Taq-e Bostan use Mithra in their investiture scenes, and the fire altars of the Sasanian temples frequently show Mithra standing at the side of the king. The Bishapur reliefs, carved on the walls of the gorge above the river, are the most extensive. the Sasanian cult of Mithra at Bishapur is treated definitively by Grenet.

The Roman cult

The Roman cult of Mithras was, in its developed form, a mystery religion centred on the mithraeum, a small, cave-like sanctuary, often purpose-built but sometimes an adaptation of a cellar or a natural cave. The worshipper entered the mithraeum and participated in a graded initiation, a sacred meal, and the contemplation of the central image: the tauroctony, in which Mithras, in a pointed cap and cloak, kneels on the back of a bull, pulls its head back with one hand, and plunges a dagger into its neck. From the wound, ears of wheat grow. A dog and a snake drink the blood. A scorpion attacks the bull’s genitals. Sol and Luna, the sun and the moon, look on from above. The image is, in some sense, the cult in a single picture.

The seven grades of initiation — Corax (Raven), Nymphus (Bridegroom), Miles (Soldier), Leo (Lion), Perses (Persian), Heliodromus (Sun-runner), Pater (Father) — are attested in inscriptions and in the Mithras Liturgy of the Greek magical papyri (PGM IV.475–829). Franz Cumont, in Textes et monuments figurés relatifs aux mystères de Mithra (1894–1900), assigned the grades to the seven planets, with the seven initiations as a ladder of ascent through the planetary spheres. This is the famous “planetary ladder” reading. Beck, in The Religion of the Mithras Cult (2006), has argued that Cumont’s scheme is more secure for Perses and Heliodromus than for the rest; the planetary correspondences of Corax, Nymphus, and Leo are best treated as insecure. I find Beck’s caution the right reading; the seven-planets reading is a useful hypothesis, not a fact.

The mithraeum was, as a rule, an elongated room with benches along the side walls and an apse at one end, in which the tauroctony relief or painting was set. The floor was sometimes covered with sand or with a pavement of opus sectile; the walls were decorated with scenes from the Mithraic myth, with zodiacs, with planetary symbols. The famous mithraeum under the Basilica of San Clemente in Rome (rediscovered in the 1950s and now re-reburied under the basilica), the mithraeum of Santa Prisca on the Aventine, the mithraea of Ostia Antica, the mithraeum of Carrawburgh on Hadrian’s Wall, the mithraea of Saarburg in Germany, the mithraeum of Sidon in Lebanon, the mithraeum of Dura-Europus in Syria — all have this basic form, with variations. The Santa Prisca mithraeum, excavated in the 1930s under the German Archaeological Institute and re-excavated by the Roman authorities in the 1960s, is the most extensively painted of the Roman examples; the magnes inscription found in the apse names the seven grades in their Greek-Latin form.

The initiation was a series of trials, sometimes called the pericula in the Latin sources. The candidate was blindfolded, threatened with swords, exposed to fire and cold, and bound with ropes. The Mithras Liturgy in the Greek magical papyri (PGM IV.475–829) gives a liturgy that is probably Mithraic in origin, though heavily Hellenised, and includes the soul’s ascent through the planetary spheres. The sacred meal, the communion, in which the initiates shared bread, water, and possibly wine, was the central ritual of the cult. Ancient and modern writers alike have compared it with the Christian Eucharist. Justin Martyr’s First Apology (c. 155 CE) makes the comparison explicit and, of course, polemical.

Mithras and the imperial Sol Invictus

The cult of Mithras reached its peak in the late second and third centuries. The emperors Commodus (180–192), Septimius Severus (193–211), Caracalla (198–217), and Diocletian (284–305) all patronised the cult. A mithraeum was the centre of religious life for many of the equites, the imperial freedmen, and the rank-and-file soldiers of the Roman army; the cult’s presence in the eastern legions and the auxiliary forts is one reason the mithraea cluster along the Roman frontiers.

The relationship between Mithraism and the imperial Sol Invictus, the “Unconquered Sun,” is debated. Aurelian’s dedication of a temple to Sol Invicus in 274 CE, and the prominence of the sun god on the coinage of Constantine and his successors, gave the Sol cult a quasi-official status, and the figure of Deus Sol Invictus Mithras appears in dedications of the period. Whether this represents a fusion of the two cults or a parallel cult that happened to share a solar vocabulary is a question without a settled answer. Beck makes the case that the two are distinct. I think the question is, in part, a definitional one: a Mithraea was a Mithraea, a Sol temple was a Sol temple, but the epithet Sol Invictus was portable.

The decline

The cult was in retreat by the late fourth century. Constantine, who gave Christianity its privileged status in 313, also favoured Mithras earlier in his career; the famous vision at the Milvian Bridge in 312 is reported by Lactantius without the in hoc signo detail that Eusebius adds. The Christian emperors of the fourth century — Constantius II, Gratian, Theodosius — closed the temples, destroyed the mithraea, and confiscated the property. The mithraeum of San Clemente in Rome was destroyed in the early fourth century; the mithraeum of Hawarte in Syria was deliberately wrecked in the early 380s, the heads of the tauroctony relief chiselled off with intent. The cult may have survived in some form into the fifth or sixth century in remote areas, and the figure of the Magus lived on in Western literature as a type of the Persian sage.

The parallels with early Christianity are striking and were drawn by the church fathers themselves. Tertullian, in De Praescriptione (c. 200 CE), and Justin Martyr, in the First Apology, both draw the comparison. Whether the similarities — graded initiation, sacred meal, saviour-god, dies natalis, iconography of light — are evidence of direct dependence, parallel development from shared Hellenistic roots, or deliberate imitation on one side or the other is one of the great questions in late antique religious history. The honest answer, I think, is that we don’t know, and the literature on it is large and inconclusive.

For further reading

  • Clauss, Manfred. The Roman Cult of Mithras: A New Approach (2000).
  • Beck, Roger. The Religion of the Mithras Cult in the Greek and Latin Literature (2006).
  • Walsh, David. The Cult of Mithras in Late Antiquity (2019).
  • Gordon, Richard. “The Roman Empire and the Cult of Mithras” in A Companion to Roman Religion (2007).
  • Grenet, Frantz. The Encyclopaedia Iranica entries on Mithra and on the Bishapur reliefs.
  • Ulansey, David. The Origins of the Mithraic Mysteries (1989). The cosmological reading, provocative but largely discredited on the details.
  • Turcan, Robert. The Cults of the Roman Empire (1996, English 1996).
  • Beck on the planets, contra Cumont: Beck, “Cumont and the Planet-Schemes of the Mithraic Grades,” in Journal of Roman Studies 1996.