Rome was influenced by Greek culture and, later on, these Greco-Roman culture spread to most of the western world. Rome has always been tolerant to foreign gods, religious practices, and cults that were integrated without problem in the local structure and customs. The Grecian Bacchus worship had spread to Rome and the whole of Italy and numerous members were initiated into secret societies promoting the worship of this god, who was assumed to provide life after death to its members. They were accused of hard drinking, sexual promiscuity, and even symbolic murders. These cults were suppressed in 186 AD. Around 200 BC the Great Mother of the Gods, Cybele, and her husband, Attis, were described as Roman gods. This cult too provided hope for life after death. Orphic and Dionysian cults, whose ideas were similar, met in secret in the Roman catacombs near Porta Maggiore in Rome.
The cult of the Egyptian goddess Isis was also practised in Rome from the time of the Emperor Augustus at the beginning of the Christian era, and during the first and second century AD. The cult of the Persian God of Light, Mithra, was introduced in Rome in the second century AD. This cult was concerned with the origin of life. A sacred bull was killed and his death was believed to give birth to the sky, the planets, the earth, the animals, and the plants. As a result Mithra was seen as the creator of life. Adonis (a god related to Osiris), the God of Vegetation from Byblos (modern Lebanon), and his partner, Atargatis (identified with Aphrodite by the Greek), were also worshipped in Rome. In the third century AD Sol, the Syrian Sun God, could have become the main god of the Roman Empire under the influence of the Emperor Aurelian. In addition Judaism and Christianity took roots in Rome during the early centuries of the Christian era, at the same time that the Mysteries reached their greatest popularity. This could be explained by the fact that these religions and the mysteries had many features in common, due to their parallel development from similar origins. Membership in these mysteries, but also in Christianity, required a long period of preparation followed by a ceremony of initiation involving fasting, baptism (seen as purification by water), banquet, prayers, etc.