Battle of Fontenoy (841)

Contention over the division of the Carolingian Empire between the three surviving sons of Louis the Pious culminated in the decisive Battle of Event locality::Fontenoy, near Auxerre, on the Event date::25 June 841. It was a defeat for the allied forces of Lothair I of Italy and Pepin II of Aquitaine and a victory for Charles the Bald and Louis the German.

Background
Louis the Pious throughout his long reign had entreated to divide his empire meritoriously amongst his sons—all his sons—as it was required by the Salic Law of the Franks. With the late-born Charles, his attempts led to civil wars which culminated in his vindicating defeat of his last rebellious son, Louis, in 839. At Worms, on 30 May that year, he divided his empire for the last time, giving Lothair the kingdom he already held (Italy) and the imperial title, with all the other lands of the east and Charles receiving all the lands of the west. Louis was left with Bavaria while Pepin, his grandson, was left out of the inheritance.

On 24 July 840 in Strasbourg, Lothair precipitated a new civil war by declaring his imperium over all the lands of the empire and, joining with his nephew Pepin, attacked the Loire Valley. The barons of Burgundy divided over allegiance to Charles and Lothair. Ermenaud III of Auxerre, Arnoul of Sens, and Audri of Autun pledged themselves for Lothair, while Guerin of Provence and Aubert of Avallon remained with Charles. Girard II, Count of Paris, Lothair's brother-in-law, joined Lothair also. In March 841, the Burgundians faithful to Charles accompanied Guerin to join him and in May, Louis of Bavaria and his troops met Charles army at Châlons-sur-Marne. In June, Pepin finally joined with Lothair in Auxerre.

The battle
The two armies, of about 150,000 men each, met on 25 June. According to tradition, Charles established his camp at Thury, on the hill of Roichat. Lothair and Pepin initiated battle and took the upper hand until the arrival of Guerin and his army of Provençals. While Pepin and his contingent continued to push back Charles men, Lothair was slowly pushed back himself by Louis the German and the Provençals. Finally, when victory seemed sure for Charles, Bernard of Septimania entered the conflict on his side and the victory became a rout. A total of 40,000 men died, including Gerard of Auvergne and Ricwin of Nantes, who fell at Charles' side.

"Neither dew nor showers nor rain ever fell again on that field where the most battle-hardened warriors had perished mourned by their mothers, their sisters, their brothers, and their friends. On Charles' side and Louis too, the fields were white with the linen habits of the dead as they might have been with birds in the autumn."

In spite of his personal gallantry, Lothair was defeated and fled to his capital of Aachen. With fresh troops he entered upon a war of plunder, but the forces of his brothers were too strong for him, and taking with him such treasure as he could collect, he abandoned to them his capital.