Chosen By God chapter 1

The Frankish king Charlemagne had a good standing with the pope, this good standing would earn him the title Imperator Romanorum

You see, the pope at this time was Leo III and he was low class with no friends in high places, people sought to “persuade” him t resign. After hired thugs nearly tore his eyes and tongue out he fled Rome and went to Charlemagne for protection. He later returned to Rome under Frankish guard. For Charlemagne’s service the pope crowned him Emperor of the Romans, however, this was controversial to say the least as another monarch was already emperor of the Romans, you see, Empress Irene led the Byzantine empire, an eastern descendant of the Roman Empire formed after the Western Roman Empire fell to barbarian invasions, already held the title Emperor of Romans as the byzantines saw themselves as the same political entity since the founding of Rome, now, ultimately due to the fact that even though previously the church had endorsed this and maintained that the Emperor in Constantinople was the rightful ruler of all former Roman lands. But since the church was a patriarchal organization it couldn’t be seen supporting the claims of a woman to be Roman Empress.

-Manticore