Mithra (mĭthˈrə) [key], ancient god of Persia and India (where he was called Mitra). Until the 6th cent. B.C., Mithra was apparently a minor figure in the Zoroastrian system. Under the Achaemenids, Mithra became increasingly important, until he appeared in the 5th cent. B.C. as the principal Persian deity, the god of light and wisdom, closely associated with the sun. His cult expanded through the Middle East into Europe and became a worldwide religion, called Mithraism. This was one of the great religions of the Roman Empire, and in the 2d cent. A.D. it was more general than Christianity. Mithraism found widest favor among the Roman legions, for whom Mithra (or Mithras in Latin and Greek) was the ideal divine comrade and fighter. The fundamental aspect of the Mithraic system was the dualistic struggle between the forces of good and evil. Mithra, who gave to his devotees hope of blessed immortality, represented the fearless antagonist of the powers of darkness. The story of Mithra's capture and sacrifice of a sacred bull, from whose body sprang all the beneficent things of the earth, was a central cultic myth. The ethics of Mithraism were rigorous; fasting and continence were strongly prescribed. The rituals, highly secret and restricted to men only, included many of the sacramental forms common to the mystery religions (e.g., baptism and the sacred banquet). Mithraism, which bore many similarities to Christianity, declined rapidly in the late 3d cent. A.D.
See F. Cumont, The Mysteries of Mithra (reissued, 1956) and M. J. Vumaseren, Mithras, the Secret God (1963).