Lothar I in the context of "Carolingian civil war"

The Carolingian civil war was a violent crisis over the succession to the Carolingian Empire following the death of Emperor Louis the Pious in June 840 and lasting until the Treaty of Verdun in August 843. Louis's eldest son, the emperor Lothar I, laid claim to an undivided empire, while his younger brothers Louis the German and Charles the Bald sought large kingdoms of their own on the basis of previous divisions planned by the late emperor. Their nephew, Pippin II, laid claim to Aquitaine.

After Louis the Pious's death, Lothar moved immediately to disregard the division of the empire and secure for himself his father's imperial position. He reached out to Pippin in Aquitaine for support against Charles. Not content with Bavaria alone, Louis the German occupied the Rhineland laying claim to all of Germania. The first military move of the budding civil war was Lothar's campaign that forced Louis from the Rhineland in August. It increased Lothar's prestige in the east, but ended in an armistice. Lothar then marched to the Seine in September, laying claim to Neustria, before reaching a truce with Charles.