It is somewhat of an accident that the ‘West’ became Christianized. It might have been just as likely that the Roman Emperor Constantine may have had some sympathies with another popular Roman religion that also originated in the Roman eastern provinces: Mithraism. Mithraism was related to Persian Zoroastrianism, but it emerged as its own offshoot in the same years Christianity was spreading through the Roman world. There are tantalizing remains of Mithraic cults in Rome, one of them this altar now found deep underground under the church of San Clemente. It shows the typical Mithraean scene, of the hero Mithras jumping up on a bull and stabbing a knife into its neck.