The Germanic tribes pillaged Western portions of The Empire for centuries. There was no respite in the cities. But Christianity grew in the region until Church formally joined with State in the year 800 (when Charlemagne was crowned Holy Roman Emperor). All Christians in the West did not follow the Nicaean Creed and were Arians. And indeed, it was not until the Baptism of The Frank Clovis in 496 that there was an authentically Christian king in Western Europe outside of Ireland. Ireland indeed fostered learning and the Latin language at a time when the traditional Roman life on the continent was in serve jeopardy.
Saint Patrick can certainly be credited with igniting this Christian fire in the Western Isles. A Briton, he was captured and imprisoned and taken to Ireland. After imprisonment of six years, he was fully converted to The Faith and was sent to Auxerre France to study. He was consecrated a bishop by Maximus of Tourin, and sent to Ireland, where he ministered for some 30 years.
Many other Irish saints contributed to the flourishing of Christianity in the country. Saints Kevin, Bridget, Finnian, and Columba were among these holy individuals. Saint Columba - along with Saint Columbanos - helped further the religion in Britian and on the continent respectively. Saint Columba established a monastery at Iona, which was the center point of Christians conversions in the Scottish Highlands. Saint Aidan, also, was a student at Iona; he went on to establish the monastery at Lindisfarne, which procured the great text, " The Lindisfarne Gospels." Britain had much help from Rome in the late 5th Century when Gregory the Great sent Saint Augustine of Canterbury to minister to Christians. Two liturgical rites were used at this time in Britain, and it was decided that the Roman Rite was to be the principal rite. This occurred at The Synod of Whitby (664).
In Ravena, the Ostrogothic King Theodoric believed strongly in Arianism. This is a characteristic of the city for the for the majority of the 5th Century. Arianism is the belief that the Second Person of the Holy Trinity was made by God the Father, that He is not of the same essence or substance as God the Father as well. Ravena had been made the capitol of the Western Empire by Honorius, who moved it from modern-day Milan. The town's population was approximately 50,000 in the Mid 400s. Justinian's mighty general Belsarius came in the early 500's to knock Arianism in Northern Italy to its knees, and thus he did in 539.
Justinian was avowed to replace the Arian churches with Orthodox ones, the Arian baptistries in exchange for ones to be used by Christians faithful to the Nicean Creed. The Basilica of San Vitali is perhaps the greatest structure of all these churches in Ravenna, and was complected only some 10 years after Belasarius's conquest. Enjoy a self-produced video about San Vitali and his basilica. Sadly you will have to copy and paste the link for now. YouTube is only allowing us commoners to post "Shorts." Why would you depart from a Multi-Billion Dollar concept?
Photo Credit: Berthold Werner, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=50404090
Now we continue to Saint Gregory, Saint Ambrose, Saint Jerome, then to Christianity in Brittiana and on the Iberian Peninsula.