Why was the Holy Roman Empire not called by that exact name when Charlemagne was crowned?

When Charlemagne was crowned in 800 CE, the title "Holy Roman Empire" did not exist because the designation was not used until the 13th century. At the time of his coronation by Pope Leo III, Charlemagne was proclaimed "emperor of the Romans," a title intended to restore the Roman Empire in the West and recognize his role as the guardian of Christendom.1234

The term "Holy Roman Empire" is anachronistic when applied to the Carolingian period. The evolution of the name occurred much later, influenced by several historical developments:1

• 12th Century: The concept of a "holy empire" (sacrum imperium) emerged during the reign of Frederick Barbarossa as a way to assert that the empire was a divinely ordained entity independent of the papacy.1
• 13th Century: The specific title "Holy Roman Empire" finally appeared during the power struggles between the Hohenstaufen dynasty and the papacy.1
• 15th Century: The title further evolved into "Holy Roman Empire of the German Nation" to reflect the empire's increasingly German focus.1

Therefore, applying the name to Charlemagne's reign is historically inaccurate, as the title only emerged centuries after his death.1