What was the transition of religion in rome. What did Romans practice first and what did they change to?

Initially, ancient Romans practiced polytheism, worshipping a pantheon of gods and goddesses, including Jupiter, Mars, and Venus, often incorporating rituals and sacrifices to secure favor. Over time, particularly from the 1st century CE onwards, the rise of Christianity marked a significant shift as it spread throughout the empire, appealing to various social classes. By the early 4th century, under Emperor Constantine, Christianity was legalized and eventually became the official religion of the Roman Empire, leading to the decline of traditional Roman pagan practices. This transition reflected broader changes in cultural, social, and political dynamics within the empire.