西フランク王国
In medieval history, West Francia (Medieval Latin: ) or the Kingdom of the West Franks () refers to the western part of the Frankish Empire established by Charlemagne. It represents the earliest stage of the Kingdom of France, lasting from about 840 until 987. West Francia emerged from the partition of the Carolingian Empire in 843 under the Treaty of Verdun following the death of Charlemagne's son, Louis the Pious.