Annals of Fulda: Battle of Fontenay (841) » De Re Militari

On June 25, 841, at the Battle at Fontenay, Louis and Charles beat their brother Lotharius I. From the article:

"Battle of Fontenay (841) » De Re Militari
The Annals of Fulda are the principal narrative source written from a perspective east of the Rhine for the period in which the Carolingian Empire gave way to a number of successor kingdoms. The text covers the period from the last years of unitary Frankish rule under Louis the Pious up to the end of effective Carolingian rule in east Francia in 900. The section translated below gives the accounts for the years 840 and 841, which saw the death of Louis the Pious, and the struggle over his kingdom by his three sons – Lothar I, Louis the German, and Charles the Bald. The later two sons formed an alliance against Lothar, andin June 841, the two sides fought an indecisive battle at Fontenay. Two years later, the Treaty of Verdun partitioned the kingdom into three states, one for each son.

Year 840

Louis the German, the emperor’s son, took possession of the part of the Empire lying beyond the Rhine as if it were his by right. He won the support of many East Franks by his prudent conduct, and marched through Alemannia to Frankfort. The emperor, learning this, was forced to return from Aquitaine, leaving his business there unfinished. He sent his brother Druogo, the arch-chaplain, Count Albert, and many others before him to guard the west bank of the Rhine; then he himself followed and celebrated Easter at Aix-la-Chapelle. About this time, night after night, a strange glow appeared in the air, in fashion like a beam, in the southeast, and another arising from the northwest. The two joined together and formed a cone and presented an appearance like clotted blood at the zenith.

After Easter the emperor gathered an army and pursued his son through Thuringia up to the frontiers of the barbarians. He drove him out of the imperial territory and forced him to make a difficult march homeward to Bavaria through the land of the Slavs. The emperor himself set all things in order in that region, and then returned to the royal town of Salz, and celebrated there the Rogation Days and the festival of our Lord’s Ascension. On the very day before the Ascension of our Lord, i.e. on the twelfth of May, there was an eclipse of the sun at about the seventh and eighth hour – so completely was the sun obscured that the stars were seen and the color of things on earth was changed.

In these days the emperor fell ill and began to waste away. He was taken on a ship down the Main to Frankfort, and from there after a few days to an island in the Rhine near Ingilenheim. His illness steadily increased upon him, and on the twentieth of June he ended his life. His body was brought to the city of Metz and buried with all due honor in the basilica of St. Arnulf the Confessor.

Lothar, who came from Italy too late [to see his father], was accepted by the Franks to rule over them in his father’s stead. For men say the dying emperor had designated him as the one who should hold after him the helm of the state, and had sent him the royal insignia – the scepter of the Empire and the crown.

Lothar’s brothers did not agree, however, to this arrangement, and they made ready to rebel against him. He went with his army to the precincts of Mayence, and there his brother Louis marched to meet him with a strong following of East Franks. They, however, agreed together to postpone decisive action until another time; and Lothar marched northward to meet Charles the Bald. Meanwhile, Louis bound to his cause by an oath of fidelity the East Franks, the Alemannians, the Saxons, and the Thuringians.

Year 841

Meanwhile Lothar placed garrisons along the Rhine and prepared to secure the east bank against an invasion from the west. He heard, through a messenger, of Louis’ hostile measures, and, giving up pursuing Charles, he turned about, and at the beginning of the month of April crossed the Rhine secretly at Worms with all his army. Louis was betrayed by some of his followers and, almost surrounded by the army of Lothar, he was forced to retreat to Bavaria.

The emperor placed guards whom he believed he could trust in those regions, and then turned his energy and his forces once more against Charles, who had already planned to establish a camp beyond the Maas. Louis was summoned to aid Charles and came by way of Alemannia. There the counts to whom Lothar had entrusted the defense of that region met Louis with an army. They gave battle on the thirteenth of May. Count Adalbert, who had stirred up the strife, was killed; and with him a countless number of men were laid low.

Louis, victor in this encounter, crossed the Rhine and hastened toward Gaul to aid his brother Charles. The three brothers met in Auxerre, near Fontenay. They could not agree to divide the Empire because Lothar, who wished to be sole monarch, was opposed to it. So they agreed that the case should be decided by the power of the sword and so proved by the judgment of God. On the twenty-fifth of June a great battle was fought between them, and the blood shed on both sides was so great that the present age remembers no such carnage among the Frankish people before. On the same day Lothar began a retreat to his city of Aix-la-Chapelle. Louis and Charles seized his camp and collected and buried the bodies of their slain. They then parted; Charles remained in the west and Louis went in the month of August to the royal town Salz.

Lothar again collected his forces from all sides. He went to Mayence and ordered the Saxons, with his little son Lothar, to meet him at Speyer. He himself crossed the Rhine, intending to pursue his brother Louis to the confines of the outlying nations. He returned to Worms, unsuccessful. He celebrated there the marriage of his daughter, and then marched toward Gaul to subdue Charles. He spent the whole winter in fruitless effort and strife and then returned to Aix. On the twenty-fifth of December a comet appeared in the sign of Aquarius.

This text was translated in Readings in European History, by James Harvey Robinson (Boston, 1904). The Annals of Fulda have been completely translated by Timothy Reuter (Manchester University Press, 1991)."