Italy

The Italian peninsula holds a religious history of two great acts: it was the heart of Roman religion and empire, and it became the seat of Western Christianity. Roman religion was, at its civic core, a matter of pax deorum, keeping right relations with the gods through scrupulous public ritual, augury, and sacrifice, on which the safety of the state depended, overlaid on an older Italic and Etruscan substratum and progressively identified with the Greek pantheon. But the religious life of Roman Italy was famously absorptive: it drew in the mystery cults of the wider Mediterranean, including Mithraism, the initiatory cult of the bull-slaying god popular among soldiers, whose underground temples dot the empire, and the worship of Cybele and Isis. Italy was also the setting (though not the origin) of Pythagoreanism, the mystical-mathematical brotherhood founded by the Greek Pythagoras in the Greek cities of the south.

The peninsula's second act is Christianity: Rome, where Peter and Paul were martyred, became the seat of the bishop who claimed primacy over the whole Church, and the Vatican the centre of Roman Catholicism for the world's largest body of Christians. From the catacombs of the persecuted early Church to the basilicas of the papacy and the art of the Renaissance, Italy carries the whole arc from pagan Rome to the capital of Latin Christendom.

Roman religion was a matter of correct performance rather than of belief, and its practitioners wrote almost nothing explaining it, because the priesthoods were public offices and the procedures were kept in archives rather than published as teaching.

Most of what is known about the older layers therefore comes from antiquarians of the late Republic and after, writing about practices already archaic in their own day and often no longer understood. Varro's great survey of religious antiquities is the outstanding case, and it does not survive. It is known through quotation, and its most extensive quoter is Augustine, who was using it to demonstrate that Roman religion was absurd. A significant part of what the modern world knows about the gods of Rome is preserved inside a Christian argument against them.

The Etruscan layer beneath is worse served. Etruscan religious books existed and are lost; the language is read only partially; and the discipline of reading livers and lightning that Rome took from Etruria is known largely from Roman descriptions of it. A bronze model of a sheep's liver marked with divine names is one of the few direct witnesses.

Against all this stands an unusually good material record. Temples, inscriptions, calendars carved in stone and the recovered towns of the Bay of Naples give the practice a physical presence the textual sources cannot. Where the antiquarians and the archaeology disagree, the archaeology is usually the safer guide.