Charlemagne was the most important Carolingian ruler who created a sizable Carolingian Empire during the late 8th century. He was of Frankish descent and was the first ruler since the fall of the Western Roman Empire to assume the title of Emperor in Western Europe.
During his reign, Frankish control expanded out from Francia to Saxonia, Bavaria, Iberian region, Italy and other neighbouring regions. The Empire forged under his reign from 768 to 814 left lasting impact on the outlook of Europe for the millennia to come.
Charlemagne became the King of the Franks in 768. At the time, the Franks had a highly organised and efficient military machine. Charlemagne first set to establish his rule in the Frankish realm. To this end, he subdued the rebellion in Aquitaine.
By 774, he had invaded the Lombard kingdom in Italy on the behest of the Pope and had been crowned the King of Italy. However, it was mostly the region of northern Italy that remained in his possession while southern Italy continued to remain outside of Frankish influence.
Charlemagne invaded and added several key territories to his original Frankish realm. By 774, this included northern Italy. From 773 to 804, Charlemagne launched a long series of battles in Saxonia with the intent of subduing the Saxons. He was successful in defeating the Saxons in most confrontations and successfully invaded the region, Christianising the Saxons in the process.
In the south, Charlemagne conquered the islands of Corsica and Sardinia. He also launched campaigns along the Spanish border and into the Iberian regions controlled by the Moors. Consequently, he was able to extend Frankish borders into the Spanish region.
By 800, Charlemagne had an Empire that stretched from Saxonia and Bavaria in the East to Spain in the West and Corsica in the South. It included most of modern-day France, Germany, Italy and many other neighbouring territories.
In 800, Charlemagne agreed to help a helpless Pope who was forced to flee Rome. He marched into Rome, reinstated the Pope and was consequently crowned the “Emperor of the Romans” by the Pope. This ushered in the age of Empire in Western Europe for the first time since the fall of the Western Roman Empire. This also propped up Charlemagne as a rival claimant to the Byzantine Emperor as heir to the Roman Empire.
The age of Charlemagne was the most glorious period of Frankish dominance in Western Europe. It was during his reign that the Frankish realm reached its maximum size. When he died in 814, he had to divide his Empire into his sons as per Frankish traditions. These divisions laid the foundations of the subsequent kingdoms of France and Germany. The division also began a process of disintegration of Frankish power and might which culminated in 887 with the end of Frankish rule in most of Western Europe.