st.Patrick is the famous one,we know every little about his life and works, the roman catholic church,the Celtic monks,saint cadoc,saint columban and so on,there are many good books on Celtic Christianity,this is a start and i could write a paper on this matter,so leave a message on my board and i can leave a couple titles for you.georgeoverton .
Kings and Monasteries helped to spread Christianity.
432AD
Paul
Paul of Tarsus, who was previously known as Saul spread Christianity as the first Christian missionary, or person who spreads their belief to non-believers. He travelled across the Roman Empire, sending Christian messages to gentiles and non-Jewish communities as well as to Jews. This allowed more people to follow the faith. He preached about Christianity in new areas where no one had preached before, and established Christianity there.
clovis helped spread christianity by making it the only legal religion
The apostle Paul spread Christianity throughout the Mediterranean regionSaint Patrick spread Christianity throughout Ireland!
Christianity
Kings and Monasteries helped to spread Christianity.
Missionaries
Charlemagne helped spread Christianity throughout the Frankish Empire and the lands he conquered. He spread Christianity through both peaceful conversion efforts and military conquests.
St. Patrick spread Christianity in Ireland.
They built the Vatican.