The Middle ages
The fall of the western Roman Empire left a void in western Europe. That void was slowly filled by a new medieval European civilization. That civilization had at its center the Christian church and a continued appreciation of it Greco-Roman Tradition. The immediate successors to the Rome werer the Germanic Kingdoms . These varied from the Visigoth Kingdom of Italy and the Frankish Kingdom. The Frankish Kingdom was the most long lasting of them. Throughout this period Christianity spread throughout Europe.
In 768 Charles the Great who became known as Charlemagne came to power. Over a period of 20 years he expanded his empire to cover most of Western Europe from France through Germany down to Rome. With the death of Charlemagne his empire called the Carolingian Empire slowly disbanded. It was followed by two centuries of invasions of Europe by non Christian groups. These groups included the Muslims from the South, the Magyars from the West and the Vikings from the North.