Christianity in the Roman Empire

Religion in ancient Rome includes the ancestral ethnic religion of the city of Rome that the Romans used to define themselves as a people, as well as the religious practices of peoples brought under Roman rule, in so far as they became widely followed in Rome and Italy. The Romans thought of themselves as highly religious, and attributed their success as a world power to their collective piety (pietas) in maintaining good relations with the gods. The Romans are known for the great number of deities they honored, a capacity that earned the mockery of early Christian polemicists.

The presence of Greeks on the Italian peninsula from the beginning of the historical period influenced Roman culture, introducing some religious practices that became as fundamental as the cult of Apollo. The Romans looked for common ground between their major gods and those of the Greeks (interpretatio graeca), adapting Greek myths and iconography for Latin literature and Roman art, as the Etruscans had. Etruscan religion was also a major influence, particularly on the practice of augury. According to legends, most of Rome's religious institutions could be traced to its founders, particularly Numa Pompilius, the Sabine second king of Rome, who negotiated directly with the gods. This archaic religion was the foundation of the mos maiorum, "the way of the ancestors" or simply "tradition", viewed as central to Roman identity.

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