In 814, Charlemagne the Great, King of the Franks, and the Emperor of the Romans died.
He left his vast Carolingian Empire to his son Louis the Pious. While still a ruler, Louis divided up the realm into his three sons, Lothair I, Louis the German, and Charles the Bald.
Lothair I was granted the most degree of authority initially but he had considerably lost his influence by the time Louis the Pious died.
Upon the death of Louis, Lothair immediately sought to extend his authority over the whole kingdom.
His two brothers contest this which led to a fierce civil war in which Lothair was defeated. The Treaty of Verdun was signed to conclude the war.
The Battle of Fontenoy was fought in 841. It was the culmination of the three-year Carolingian Civil War.
At one side were Lothair I and Pepin II’s forces. On the other side were the forces of Lothair’s brothers, Charles the Bald and Louis the German.
Lothair and Pepin were decisively defeated. This defeat played a major role in forcing the two to sign a treaty of peace.
The primary purpose of the Treaty of Verdun was to decide how each son of Louis the Pious would rule.
The treaty was meant to define the territories for each son. It also served the purpose of subduing the influence and ambition of Lothair I after he had been decisively defeated by his two brothers.
The Oaths of Strasbourg were pledges of alliances declared by the brothers of Lothair I, Louis the German, and Charles the Bald.
In these pledges, the two brothers declared that Lothair I was unfit for rule and that they would jointly oppose his military campaigns.
The Oaths of Strasbourg played an important role in forcing Lothair I to sign a treaty.
The Treaty of Verdun was signed to resolve the Carolingian Civil War.
This treaty clearly defined the territories and spheres of influence for the three sons of Louis the Pious. As per this treaty, Lothair I received the kingdom of Middle Francia.
This kingdom extended over the lands of Burgundy, Provence, Lorraine, Alsace, the Kingdom of Italy, and the Low Countries.
Lothair also retained his title of emperor, although the title only conferred nominal powers on him. Charles the Bald was declared the ruler of West Francia. He ruled over lands that would subsequently be a part of the Kingdom of France.
Louis the German was granted rule of East Francia. This included most of the Frankish lands east of Rhine as well as Rhineland.
The Treaty of Verdun fragmented the Carolingian Empire. This fragmentation would continue for many centuries.
Rulers in East and West Francia would vie for centuries to gain control of the territories that once belonged to Middle Francia.
Territories like Alsace-Lorraine would continue to be disputed and switch hands all the way until the 20th century.