Mithraism is the ancient Roman mystery cult of the god Mithras. Roman worship of Mithras began sometime during the early Roman empire, perhaps during the late first century of the Common Era (hereafter CE), and flourished from the second through the fourth centuries CE. While it is fairly certain that Romans encountered worship of the deity Mithras as part of Zoroastrianism in the eastern provinces of the empire, particularly in Asia Minor (now modern Turkey), the exact origins of cult practices in the Roman cult of Mithras remain controversial (see below). The evidence for this cult is mostly archaeological, consisting of the remains of mithraic temples, dedicatory inscriptions, and iconographic representations of the god and other aspects of the cult in stone sculpture, sculpted stone relief, wall painting, and mosaic. There is very little literary evidence pertaining to the cult.
The Deity: Mitra, Mithra, Mithras
Mithras is the Roman name for the Indo-Iranian god Mitra, or Mithra, as he was called by the Persians. Mitra is part of the Hindu pantheon, and Mithra is one of several yazatas (minor deities) under Ahura-Mazda in the Zoroastrian pantheon. Mithra is the god of the airy light between heaven and earth, but he is also associated with the light of the sun, and with contracts and mediation. Neither in Hinduism nor in Zoroastrianism did Mitra/Mithra have his own cult. Mitra is mentioned in the Hindu Vedas, while Mithra is is the subject of Yashts (hymns) in the Zoroastrian Avesta, a text compiled during the Sassanian period (224-640 CE) to preserve a much older oral tradition.
Possible Eastern Origins of the Roman Cult
The precise relationship between the Roman cult of Mithras as it developed during the empire and the Mitra and Mithra of the Hindu and Zoroastrian pantheons, respectively, is unclear. The theory that Roman Mithraism had its roots in Zoroastrianism was first put forward by Franz Cumont, a Belgian scholar, in his two-volume publication Textes et monuments figurés relatifs aux mystères de Mithra in 1896 and 1899. Cumont compiled a catalogue of every known mithraic temple, monument, inscription, and literary passage relating to Mithras and claimed on the basis of his study of this body of evidence that Roman Mithras was, ultimately, Zoroastrian Mithra. Cumont argued by extension that if Roman Mithras had Iranian roots, the cult of Mithraism must have originated in the eastern provinces of the Roman empire and spread westward with legionaries in the Roman army, merchants from eastern provinces (often lumped under the broad misnomer "Syrians"), freedmen in the imperial bureaucracy, and slaves.
Cumont himself recognized possible flaws in his theory. The most obvious is that there is little evidence for a Zoroastrian cult of Mithra (Cumont 1956), and certainly none that suggests that Zoroastrian worship of Mithra used the liturgy or the well-devoloped iconography found in the Roman cult of...