In this episode of The Rest Is History, the hosts dive into Charlemagne's coronation as Emperor of the Romans on Christmas Day in 800 AD. They explore whether Charlemagne was taken by surprise by Pope Leo III’s move or if it was a strategic plan to bolster Charlemagne's power during a turbulent period for both the Eastern Roman Empire and Rome itself. The discussion examines the political backdrop, highlighting the vulnerabilities of the Byzantine Empire under Empress Irene and the turmoil within the Roman papacy. The hosts assert that Charlemagne likely orchestrated the coronation to seize the opportunity created by the Eastern Empire's decline. The episode wraps up by looking at how Charlemagne's empire later fragmented due to dynastic strife and external threats from the Vikings and Saracens, eventually paving the way for the Saxon dynasty under Otto the Great—a surprising turn, given the Saxons had once been Charlemagne's foes.