A Roman incarnation of Mithraism. Mithraism entered into the Roman Empire circa 70 B.C.E. through Roman military contact with Turkey and south eastern Europe, and through the activities of Mediterranean pirates. By the 4th century C.E. Mithraism, fusing somewhat with Greek symbolism and mysticism, became the predominant and official religion of Rome, closely rivalling Christianity. The central symbol of Roman Mithraism was the Tauroctony.