Mithraism, also called the Mithraic mysteries or the Cult of Mithras, was a Roman religious tradition centered on the god Mithras. It was influenced by the worship of Mithra in ancient Iran, but the Roman version of Mithras had unique symbols and practices. The connection between Persian and Roman traditions is still uncertain. The religion was widely followed by soldiers in the Roman Empire from the 1st to the 4th century AD.

Members of Mithraism followed a system with seven levels of spiritual growth and shared meals during rituals. They called themselves "syndexioi," meaning "those united by a handshake." They gathered in underground temples called mithraea, which were often shaped like caves. These temples have been found in many places across the Roman Empire. The religion was most active in Rome and spread to regions such as North Africa, Dacia, Britain, and parts of Syria.

Mithraism was considered a competitor to early Christianity. In the 4th century, Christians persecuted Mithraists, and the religion was banned and disappeared from the Roman Empire by the end of the century.

Archaeological discoveries, such as temples, carvings, and inscriptions, have helped scholars learn about Mithraism. Common images show Mithras being born from a rock, killing a bull, and sharing a meal with the sun god Sol. About 420 sites have provided materials linked to the cult, including around 1,000 inscriptions, 700 depictions of the bull-killing scene, and 400 other monuments. It is estimated that there were at least 680 mithraea in Rome. No written texts from the religion survive, so most knowledge comes from inscriptions and brief mentions in Greek and Latin writings. The meaning of these physical remains is still unclear and debated.

Name

The word "Mithraism" is a term used today. People in ancient Rome described the practice using phrases like "Mithraic mysteries," "mysteries of Mithras," or "mysteries of the Persians." Today, some sources use terms such as "Roman Mithraism" or "Western Mithraism" to show the difference between the Roman version of this belief and the worship of Mithra in Persia.

Etymology

The name Mithras (Latin) is the same as the Greek name Μίθρας. It comes from Mithra, a god who was worshipped before Zoroastrianism existed and later became part of Zoroastrian beliefs. Scholars who study Mithraism, like Franz Cumont, have known about this connection for a long time. An early example of the Greek form of the name appears in a work from the 4th century BCE by Xenophon called Cyropaedia, which is a story about the Persian king Cyrus the Great.

The way a Latin or Greek word is written can change based on grammar rules called inflection. Evidence from ancient times shows that in Latin, people who worshipped Mithras wrote the name as "Mithras" in the nominative form. In his Greek text De Abstinentia, Porphyry mentions lost writings about Mithraic mysteries by Euboulus and Pallas. These writings suggest that the authors treated the name "Mithra" as a foreign word that did not change form.

Other languages have related names for the same deity. In Sanskrit, "mitra" is a name for the sun god, though he is more commonly known as "Surya" or "Aditya." The names "Mithra" in Iranian languages and "Mitra" in Sanskrit are believed to come from the Indo-Iranian word mitrás, which means "contract, agreement, or covenant."

Modern historians disagree about whether these names refer to the same god. John R. Hinnells believes that Mitra, Mithra, and Mithras are names for the same deity worshipped in different religions. However, David Ulansey thinks that the Mithras who is often shown slaying a bull was a new god who began being worshipped around the 1st century BCE, and the name "Mithras" was applied to him later.

Mary Boyce, a researcher who studies ancient Iranian religions, notes that even though Roman Mithraism had less connection to ancient Iranian beliefs than some people once thought, the name "Mithras" shows that these connections were still important.

Iconography

Much about the Mithras cult is known only from carvings and statues. Many people have tried to explain what these images mean.

Mithras worship in the Roman Empire often showed the god killing a bull. Other images in Roman temples include Mithras sharing a meal with the sun god Sol and scenes of Mithras emerging from a rock. However, the image of Mithras killing a bull, called the tauroctony, is always placed in the center of these scenes. Very few written records explain the religious meaning behind these images.

The image of Mithras killing a bull appears only in Roman Mithraism. According to David Ulansey, this is a major difference between Roman and Iranian traditions: "There is no evidence that the Iranian god Mithras ever killed a bull."

In every Mithraic temple, the central image shows Mithras killing a sacred bull. This image may be carved into stone or stand alone. Details such as a dog, a snake, or a scorpion may appear or not. Mithras is shown wearing Anatolian clothing and a Phrygian cap, kneeling on the bull, holding its nose with his left hand, and stabbing it with his right. He looks toward Sol, the sun god. Blood from the bull is reached for by a dog and a snake. A scorpion is near the bull's genitals. A raven is flying or sitting on the bull. Wheat stalks may appear from the bull's tail or wound. The bull is often white. Mithras sits on the bull in a strange way, with his right leg controlling the bull's hoof and his left leg resting on the bull's back or side. Two torchbearers, Cautes and Cautopates, stand on either side. Cautes holds a torch pointing upward, and Cautopates holds a torch pointing downward. Sometimes they carry shepherds' crooks instead of torches.

The scene takes place in a cave, where Mithras has brought the bull after hunting it. The cave is sometimes surrounded by a circle with the twelve signs of the zodiac. Sol, the sun god, appears at the top left, often driving a four-horse chariot. A ray of light often reaches Mithras. At the top right is Luna, the moon goddess, driving a two-horse chariot.

Some images include scenes next to the tauroctony, showing Mithras being born from a rock, performing a water miracle, hunting the bull, meeting Sol, sharing a meal with him, and riding to the heavens. In some cases, like the Santa Prisca Mithraeum in Rome, Mithras is shown nude. Some reliefs could be turned to show another scene of a feast on the other side. This suggests the tauroctony was part of a celebration, followed by the feast scene. Some temples had multiple tauroctonies, and small portable versions were likely used for private worship.

The second most important scene in Mithraic art is the banquet, where Mithras and Sol share a meal on the bull's hide. On some reliefs, a torchbearer holds a staff with two snakes (a caduceus) near an altar, where flames appear. Robert Turcan suggests this relates to the god Mercury, who guides souls in mythology, and connects the flames to the Mithraic belief about souls. Turcan also links the flames to the blood from the slain bull, which is said to release souls.

Mithras is often shown emerging from a rock as a young man, holding a dagger and torch. He is nude, wearing a Phrygian cap. In some images, he appears as a child or holds a globe or thunderbolt. Flames may come from the rock or his cap. Some statues have bases that could act as fountains, and others have the face of a water god. Mithras is sometimes shown with weapons like bows and arrows, and animals like dogs, serpents, dolphins, eagles, lions, crocodiles, lobsters, and snails are nearby. Some reliefs include a bearded figure called Oceanus, the god of water, or the gods of the four winds. These scenes may involve the four elements and gods like Victoria, Luna, Sol, and Saturn. Saturn is often shown giving Mithras a dagger used later in the tauroctony.

Cautes and Cautopates sometimes appear as shepherds. Some scenes show an amphora or variations like an egg or tree birth. Some believe Mithras' birth was celebrated with torches or candles.

A mysterious figure, called leontocephaline (lion-headed), is often found in Mithraic temples. This figure has a lion's head and a human body, wrapped by a snake or two. The snake's head often rests on the lion's head. The lion's mouth is open. The figure has four wings, two keys (or one), and a scepter. It sometimes stands on a globe with a diagonal cross. On some statues, the wings show the four seasons, and a thunderbolt is on the chest. At the base are tools of Vulcan (hammer and tongs) and Mercury (a caduceus). A rare version shows a human head and a lion's head emerging from the chest.

Although similar figures appear in Egyptian and Gnostic myths, no exact match to the leontocephaline figure has been found. Based on inscriptions, scholars think the figure's name might be Arimanius, a Latin version of Ahriman, a Zoroastrian demon. Arimanius is mentioned in Mithraic inscriptions, such as those from Ostia and Rome. Some scholars believe the figure represents Aion (time), Zurvan (eternal time), Cronus (time), or Chronos, while others think it is Ahriman or Aryaman, a more peaceful Z

Rituals and worship

According to M.J. Vermaseren and C.C. van Essen, the Mithraic New Year and the birthday of Mithras were celebrated on December 25. Beck strongly disagreed with this view. Clauss explains that the Mithraic Mysteries did not have public ceremonies. The festival of Natalis Invicti, held on December 25, was a general celebration of the Sun and not specifically tied to the Mysteries of Mithras.

Mithraic initiates were required to promise to keep secrets and remain dedicated to the faith. Mithras was considered a "warrior hero," similar to Greek heroes.

Some rituals involved reciting a catechism, where initiates answered questions about symbols and meanings. An example from the Leo grade was found on a fragmentary Egyptian papyrus (Papyrus Berolinensis 21196).

Very few Mithraic writings or firsthand accounts of rituals remain. Exceptions include the oath and catechism, and the Mithras Liturgy from 4th-century Egypt, though its connection to Mithraism has been questioned by scholars like Franz Cumont. The walls of mithraea were often whitewashed, and surviving graffiti and inscriptions on monuments are the main sources of Mithraic texts.

Archaeological findings suggest that many Mithraic rituals involved feasting. Eating utensils and food remains, including animal bones and fruit residues, are often found. Large numbers of cherry stones indicate that mid-summer (late June to early July) was a time of celebration. A bronze plaque called the Virunum album records a Mithraic festival on June 26, 184. Beck argues that this date reflects the importance of the summer solstice, a time also linked to other ancient solar festivals.

During feasts, Mithraic initiates reclined on stone benches inside the mithraeum. These spaces typically held 15 to 30 people, rarely more than 40. Similar dining rooms, called triclinia, were common in Roman temples and used by religious groups. Mithraic feasts may have served a similar purpose for Mithraists, as Roman collegia (clubs) often limited membership to specific groups. The size of a mithraeum does not always reflect the number of members.

Each mithraeum had altars at the far end, beneath the tauroctony (a relief showing Mithras killing a bull). Many altars were dedicated by initiates to Mithras as a vow or thanksgiving. Burned animal remains on altars suggest regular sacrifices, though mithraea lacked facilities for ritual slaughter. Sacrifices may have been arranged with professional religious workers. Prayers were offered to the Sun three times daily, and Sunday was considered sacred.

It is uncertain whether Mithraism had a single, unified belief system. Practices may have varied by location. Mithraic symbols are consistent, but there was no central temple or authority. Some mithraea, like those in Dura Europos, had painted scenes of prophets with scrolls, but no named Mithraic teachers are known. Initiates could move between mithraea while keeping their grades.

Mithraic temples were underground, windowless, and distinct. They were often built in basements, caves, or excavated spaces. These temples were common in the Roman Empire, found in places like Rome, Ostia, Numidia, Dalmatia, Britain, and along the Rhine and Danube rivers. They were less common in Greece, Egypt, and Syria. Walter Burkert noted that the secrecy of Mithraic rituals meant they could only be practiced in mithraea. Recent discoveries in Tienen suggest that feasting was common and the religion may not have been as secretive as once thought.

Most mithraea were small, simple, and built cheaply. The cult preferred creating new centers rather than expanding existing ones. Mithraea symbolized the cave where Mithras killed the bull. If stone vaulting was unavailable, lath and plaster were used to mimic the effect. Mithraea were often near water sources, with basins for rituals. They had entrance halls and rooms for food preparation. Surviving mithraea show the physical structures of Mithraic sacred spaces. The term "mithraeum" is modern; ancient Mithraists called their temples "speleum," "antrum," "crypta," "fanum," or "templum."

Mithraea differed greatly from other Roman temples. In typical Roman religious spaces, temples were open to the public, with altars in courtyards for worship. Mithraea were the opposite, being closed and exclusive.

The Suda, an ancient Greek encyclopedia, mentions that initiates into Mithras had to prove themselves holy and steadfast through tests. Gregory Nazianzen also refers to these tests.

There were seven grades of initiation in Mithraism, listed by St. Jerome. Manfred Clauss suggests the number seven relates to the planets. A mosaic in the Mithraeum of Felicissimus, Ostia Antica, shows these grades with symbols connected to planets. Each grade is protected by a different planetary god. The grades, in order of importance, are:

History and development

Archaeologist Maarten Vermaseren notes that evidence from Commagene in the 1st century BCE shows that people honored Mithras, but there is no mention of "the mysteries." At Mount Nemrut, King Antiochus I (69–34 BCE) built large statues showing Mithras without a beard, wearing a Phrygian cap or a Persian tiara, and dressed in Iranian clothing. Mithras was originally seated on a throne with other gods and the king. Greek inscriptions on the thrones include the name Apollo-Mithras-Helios in the genitive case (Ἀπόλλωνος Μίθρου Ἡλίου). Vermaseren also reports a Mithras cult in Fayum from the 3rd century BCE. R.D. Barnett suggests that a royal seal from King Saussatar of the Mitanni around 1450 BCE depicts Mithras killing a bull.

Scholars have debated the origins and spread of the Mithraic Mysteries, with differing views. Clauss claims the mysteries began in the 1st century CE, while Ulansey argues evidence from the middle of the 1st century BCE shows their early appearance. Plutarch wrote that pirates in Cilicia practiced "secret rites" of Mithras in 67 BCE. C.M. Daniels says it is unclear if these practices relate to the mysteries’ origins. Underground temples called mithraea first appear in archaeological records in the last quarter of the 1st century CE.

Inscriptions and monuments related to Mithraism are collected in a two-volume work by Maarten J. Vermaseren called Corpus Inscriptionum et Monumentorum Religionis Mithriacae (CIMRM). The earliest known image of Mithras killing a bull is CIMRM 593, found in Rome. The inscription credits it to Alcimus, a steward of T. Claudius Livianus. Vermaseren and Gordon believe Livianus was a Praetorian guard commander in 101 CE, placing the earliest date of the image between 98–99 CE.

Five small terracotta plaques showing a figure with a knife over a bull were found near Kerch in the Crimea. These date to the second half of the 1st century BCE, or 50 BCE–50 CE, according to Beskow, Clauss, and Beck. If these are Mithras, they may be the earliest known tauroctonies. However, the figure wears a Phrygian cap but differs from standard depictions of the scene. One plaque was found in a woman’s tomb, which adds to uncertainty about its connection to the mysteries.

An altar in Rome, near SS. Pietro e Marcellino, was inscribed by T. Flavius Hyginus, an Imperial freedman, between 80–100 CE. It honors Sol Invictus Mithras. CIMRM 2268, a broken altar from Novae/Steklen in Moesia Inferior dated to 100 CE, shows figures called Cautes and Cautopates. Other early finds include a Greek inscription from Venosia (100–150 CE), a cippus from Sidon (140–141 CE), and a military inscription from Carnuntum (before 114 CE).

C.M. Daniels states the Carnuntum inscription is the earliest Mithraic dedication in the Danube region, where Mithraism first took root alongside Italy. The earliest mithraeum outside Rome dates to 148 CE. The Mithraeum at Caesarea Maritima in Palestine is the only one there, with an inferred date. Excavations in Inveresk, Scotland (2010) found two altars to Mithras from 140 CE, believed to be the northernmost Mithraic temple in the Roman Empire.

Roger Beck lists early Mithraic sites from the 1st–2nd centuries CE. The earliest literary references to the mysteries are by Statius (80 CE) and Plutarch (100 CE). Statius’ Thebaid describes Mithras in a cave, wrestling with a horned creature, in a prayer to Phoebus. The cave is called perseis, meaning Persian. Plutarch wrote that pirates in Cilicia practiced Mithraic mysteries in the 1st century BCE. These pirates supported King Mithridates VI of Pontus during the Mithridatic Wars.

Dio Cassius (2nd–3rd century CE) mentions that during Tiridates I of Armenia’s visit to Rome under Nero, Tiridates said he revered Nero “as Mithras.” Beck suggests this event may have helped spread Mithraism in Rome. Porphyry (3rd–4th century CE) wrote in De antro nympharum that Zoroaster found a natural cave in Persia, which he dedicated to Mithras. Porphyry linked Mithras to Aries and Mars, and the bull to Venus. However, scholars like Turcan argue Porphyry’s account reflects Neoplatonist ideas, not Mithraic beliefs. Beck believes Porphyry’s work is the only clear ancient text explaining the Mithraic mysteries’ purpose. Ulansey highlights Porphyry’s confirmation of astronomy’s role in Mithraism.

In later antiquity, the Greek name for Mithras (Μίθρας) appears in texts.

Interpretations of the bull-slaying scene

According to Cumont, the image of the tauroctony (a scene where Mithras kills a bull) was a Roman and Greek representation of an event described in a 9th-century Zoroastrian text called the Bundahishn. In this text, the evil spirit Ahriman (not Mithra) kills the primordial creature Gavaevodata, which is shown as a bull. Cumont believed that a version of the myth existed where Mithras, not Ahriman, killed the bull. However, Hinnells states that no such version of the myth is known and that this idea is only a guess: "In no known Iranian text [either Zoroastrian or otherwise] does Mithra slay a bull."

David Ulansey found evidence in the mithraeum (a temple for Mithras) that may relate to the stars. He notes that the 3rd-century writer Porphyry described the cave-like temple as depicting "an image of the world" and that Zoroaster created a cave resembling the world made by Mithras. The ceiling of the Caesarea Maritima Mithraeum had traces of blue paint, which might have been used to show the sky and stars.

Beck has listed several possible celestial identities for the tauroctonous Mithras (the bull-killing Mithras) in a table. Ulansey suggests that Mithras may have been inspired by the constellation Perseus, which is near Taurus in the sky. He points to similarities between Perseus and Mithras, such as both being young heroes, carrying a dagger, and wearing a Phrygian cap. Ulansey also notes that Perseus killing the Gorgon and Mithras killing the bull both involve figures connected to caves and Persia. Michael Speidel links Mithras to the constellation Orion because of its closeness to Taurus and the way Mithras is depicted with wide shoulders, a flared garment, and a belt, resembling Orion’s shape.

Jelbert disagrees with theories that connect Mithras to specific constellations. He argues that Mithras may represent the Milky Way. He claims that Mithras’ body in the tauroctony image mirrors the path of the Milky Way between Taurus and Scorpius. Jelbert suggests that this idea fits Mithras’ role as a god of light and creation, as the Milky Way is bright and associated with soul gates at Taurus-Gemini and Scorpius-Sagittarius, believed to be where souls enter and leave the body.

Beck criticized Speidel and Ulansey for trying to match the tauroctony to star charts, calling their approach misleading. He argues that the tauroctony cannot be directly compared to a star map because Mithras does not clearly match any constellation, and the scene’s symbols may have multiple meanings. Instead, Beck believes Mithras represents the "Unconquered Sun," moving through the stars. However, Meyer suggests that the Mithras Liturgy (a text from Mithraism) supports Ulansey’s theory that Mithras is connected to the precession of the equinoxes.

Peter Chrisp states that the killing of the "sacred bull" in the tauroctony was believed to create and maintain the universe’s life force.

Comparable belief systems

The cult of Mithras was part of the way ancient Roman religion combined different beliefs. Many Mithraic temples, called Mithraea, had statues honoring gods from other religions. Inscriptions praising Mithras were also found in other religious places, such as those dedicated to Jupiter Dolichenus. Mithraism was not a replacement for other Roman religions but one of many practices. Many people who joined Mithraism also took part in public religious activities and other mystery cults.

Early Christian writers noticed similarities between Mithraic and Christian rituals but strongly criticized Mithraism. They believed Mithraic ceremonies were evil copies of Christian ones. For example, Tertullian described how Mithraic initiates were given a ritual bath before ceremonies and received a mark, possibly the letter "M," on their foreheads. He called these practices a false imitation of Christian baptism and chrismation. Justin Martyr compared Mithraic communion rituals with the Christian Eucharist.

In 1882, Ernest Renan suggested that if Christianity had not grown as it did, Mithraism might have become as widespread as modern Christianity. However, this idea has been challenged. Leonard Boyle argued that Mithraism was not a major threat to Christianity, noting that only about fifty Mithraic temples were found in Rome. J.A. Ezquerra stated that since Mithraism and Christianity had different goals, Mithraism never seriously threatened to replace Christianity. Mithraism was supported by Roman aristocrats during a time when traditional values faced challenges from rising Christianity.

Mary Boyce claimed Mithraism was a strong rival to Christianity in the West but doubted its influence in the East. F. Coarelli listed forty known or possible Mithraic temples and estimated Rome had at least 680–690 such temples. L.M. Hopfe reported over 400 Mithraic sites found across the Roman Empire, from Dura-Europos in the east to England in the west. He also suggested Mithraism may have competed with Christianity. David Ulansey thought Renan’s claim was exaggerated but acknowledged Mithraism was one of Christianity’s main competitors in the Roman Empire.