What was Charlemagne responsible for promoting across Europe?

Charlemagne played a crucial role in promoting what would become known as the Holy Roman Empire during the early Middle Ages. His reign marked a significant unification of much of Western Europe, which had been fragmented following the decline of the Roman Empire. In 800 AD, he was crowned Emperor by Pope Leo III, signifying the merging of Roman, Christian, and Germanic elements into a new political structure. This event symbolized the revival of the idea of a unified Christian empire in the West, which became central to the identity of the Holy Roman Empire.

Charlemagne's efforts included the expansion of territory through military conquests, the strengthening of the Christian church, and the promotion of learning and culture, known today as the Carolingian Renaissance. He established a system of local governance and administrative divisions to improve the management of his vast empire. Under his rule, he significantly advanced the spread of Christianity and played a pivotal role in shaping the political landscape of medieval Europe, which ultimately laid the groundwork for the later development of the Holy Roman Empire.

In contrast, the Byzantine Empire was a continuation of the eastern Roman Empire, the Ottoman Empire emerged centuries later, and the Greek city-states pertained to ancient history well before Charlemagne's time. Thus