Answer: Was crowned pope on Christmas Day, A.D. 800 / united a vast realm under the Christian faith.
Explanation:
Some historians consider Charlemagne to be one of the most significant figures of medieval Europe. Due to his military and political influences, he became the most influential figure in Western Europe. In so doing, the term "Christian Empire" he uses has become synonymous with the entire Christian West, in opposition to the Byzantine Empire. By his coronation, Charlemagne became the patron saint of the whole Christian West and the papacy. Its impact is enormous in all fields of life. His inauguration was boycotted by Byzantium, leading to war. The war ended in Aachen in 812, and Byzantium thus had to acknowledge Charles's imperial rule.
