Lotharingia

Lotharingia was a medieval kingdom and later duchy between the East and West Frankish kingdoms, named after King Lothair II. Its borders and political status shifted repeatedly.

Treaty of Verdun: The 843 agreement that divided the Carolingian Empire among the surviving sons of Emperor Louis the Pious. Its division created the middle kingdom from which Lotharingia later emerged.
Treaty of Ribemont: The 880 agreement that transferred the western portion of Lotharingia to the East Frankish king Louis the Younger. It reunited most of Lotharingia under East Frankish rule.
Carolingian Empire: The Frankish empire ruled by the Carolingian dynasty, reaching its greatest extent under Charlemagne. Its partitions produced the kingdoms from which Lotharingia arose.
Lower Lorraine: The northern duchy formed from the division of Lotharingia in the tenth century. It carried Lotharingian political traditions into the Low Countries.
Middle Francia: The Carolingian kingdom stretching from the North Sea to Italy, ruled by Emperor Lothair I after 843. Lotharingia formed in the northern portion of this larger realm.
East Francia: The eastern Frankish kingdom that developed into the kingdom of Germany. Lotharingia became a contested frontier region within its sphere of power.
Duchy of Lorraine: A duchy in the western part of the former Lotharingian realm, later known as Lorraine. It preserves the region’s name in a later territorial formation.
Upper Lorraine: The southern duchy formed from the division of Lotharingia in the tenth century. It developed into the territory later called Lorraine.
Treaty of Prüm: The 855 partition that divided Lothair I’s Middle Francia among his sons. It gave Lothair II the northern kingdom later known as Lotharingia.
West Francia: The western Frankish kingdom that developed into the kingdom of France. Its rulers repeatedly sought control over Lotharingian lands.

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Lothair IBroader topic: Its name and contested lands emerged from the division of Lothair I’s Middle Francia.