Battle of Soissons
923 CE.
Shown on the map at 49.382°, 3.324°.
The Battle of Soissons was fought on 15 June 923 between an alliance of Frankish insurgent nobles led by Robert I, elected king in an assembly the year prior, and an army composed of Lotharingians, Normans, and Carolingian forces under King Charles III's command. The battle took place at Soissons, near Aisne. Robert was killed, but his army won the war. Charles was imprisoned by Herbert II of Vermandois and held captive until his death in 929. Rudolph, Duke of Burgundy, Robert's son-in-law, succeeded him as ruler of West Francia. After Charlemagne's death, the Carolingian royal authority began to decline due to the constant invasions of the Vikings, civil wars and strife with vassals, mainly the Robertians. Since its beginning, the political situation of Charles's reign was fragile. Frankish nobility was unwilling to accept his authority. One of his few allies was Baldwin II of Flanders.
Text from the Wikipedia article Battle of Soissons (923), licensed CC BY-SA 4.0.