It could hardly be argued that Romans took to religion more than other peoples did. Yet they cherished, along with astrology and magic, a plethora of gods, old and new. A large pantheon had made room, beside the native Roman gods, for most of the renamed Greek deities; they served the main purpose of attending to various human activities. Rituals and ceremonies were performed with scrupulous precision by appointed personnel (priests, augurs, vestals) in sanctuaries, temples, and homes. Festivals and sacrifices were duly practiced, their observance being commended for the soothing effect they produced.
The Roman conquests had a double impact on the religious makeup of the region. Wherever Romans established a colony, they introduced their trinity—Jupiter, Juno, and Minerva. But they also brought home new cults. Meanwhile the state religion that had emerged at the end of the republic was revitalized by Augustus; pride of honor was given to Apollo and Artemis, and the formality unsuitably called “emperor cult” (it showed only weak religious features, if any) was introduced.The decisive development following the reign of Augustus relates to the spread of Oriental cults over the empire and in Rome itself. They answered needs unfulfilled by traditional religion, above all those relating to the afterlife and to soteriology. More will be said about them in chapter 4. Parallel to the appearance of the monarchical system of government, a certain trend toward monotheism can be perceived: More and more local deities were seen as mere manifestations of a single power. The educated Romans, skeptical as to official ceremonies and popular beliefs, and not too inclined to believe in the gods of the pantheon, generally believed in Providence.