Which individual traveled throughout the Roma empire to spread Christian faith?

The individual who traveled throughout the Roman Empire to spread the Christian faith was the apostle Paul, also known as Saint Paul. He was a key figure in the spread of Christianity in the first century and is credited with writing several of the books in the New Testament of the Bible. Paul embarked on several missionary journeys throughout the Mediterranean region, including cities in the Roman Empire, to preach the gospel and establish new Christian communities.