Why was a coin placed on a dead body?

The religion of the Romans incorporated a belief in a collection of gods and goddesses, each with their own responsibilities. For example, Mars was the god of War and Minerva the goddess of Wisdom. They thought of themselves as highly religious and attributed their success as a world power to their good relations with the gods. However, despite their initial persecution of Christians, by the time of the Fall of Rome most Romans had stopped worshiping the Roman gods and goddesses and had become Christians themselves.