Religion
The Romans were polytheists. Their gods were very similar to those of the Greeks. The main difference between them were the names, for example, the Greek god Zeus, god of the sky, was pretty much the same as Jupiter, also the god of the sky. When the Romans conquered other lands, they made those people abandon their religions and follow the one of the Romans instead.
The Pantheon The Roman Gods
Life after Death
It was the Romans' belief that after one's death, their spirit would go to the Underworld, which was ruled by Pluto. To get there, the dead needed to cross the River Styx. The deceased's family would leave a coin on the dead body, to pay Charon, the ferryman.
Christianity
Some of the old beliefs changed when Christianity was made the official religion of the Roman Empire by the Emperor Constantine in the year 400 BCE. Before then, Christians got into trouble because they refused to worship the emperor as a god. Some Christians were arrested and put to death.