Christianity began in Rome but early Christians faced persecution as they refused to worship Roman gods. Emperor Nero persecuted Christians in the first century, having some torn apart by dogs or burned alive. The earliest Christians in Rome tended to be poorer citizens and slaves, as Christianity taught equality and an afterlife in heaven. They met secretly in homes since they lacked church buildings. Persecution continued until Emperor Constantine legalized Christianity in the 4th century, though some Christians like Perpetua and Felicity still faced martyrdom for their faith in the early 3rd century.