The First Battle of Aachen was a battle during the First Viking War. Part of the Rhine Raids, the First Battle of Aachen was a wake-up call for the Byzantine and Frankish Empires. The battle ultimately resulted in the destruction of the Palace of Aachen and the death of Lothair I. The Vikings occupied the city until Atticus I pushed them out of Aachen shortly thereafter in the Second Battle of Aachen.
The Rhine Raids had all but crippled the Frankish Empire in the German areas. With the Frankish Navy faltering and the Frankish armies losing battle after battle, the late 840s were grim for the Franks. The Vikings relied on hit-and-run attacks to keep the Franks on the run. Cities, towns, and other settlements along the Rhine River were sacked by the Vikings. Utrecht and Cologne were among the prosperous cities that had been sacked by the Vikings.
In 849, the Vikings sent a large raiding party down the Meuse River.
The Vikings were only able to take their ships so far. In the spring of 849, Maastricht was sacked by the Vikings, allowing them to easily reach both Liége and Aachen. Most of the Rhine Raids only resulted in the sacking of towns. Maastricht, on the other hand, was occupied. From here, the Vikings launched raids against several other settlements before, finally, a Danish raiding party led by Ragnar Lodbrok reached Aachen.
The city defended itself valiantly, but the Vikings reached the walls and were able to breach them from the west. With the walls of Aachen breached, Vikings entered the city and took it by force, massacring citizens and taking anything of value. The Vikings burned large swaths of the city, resulting in the destruction of many houses and buildings before, finally the Palace of Aachen was ablaze. Many people assumed Lothair I was killed in battle against Ragnar Lodbrok. Recent evidence points to Lothair being killed when parts of the Palace of Aachen collapsed.
The Vikings held the city for three weeks before the Franks were able to successfully retake the city.
The First Battle of Aachen was a wake-up call for the Eastern Roman Empire and the Frankish Empire. The Franks had been focused on retaking the areas the Danes were taking near Jutland. With Aachen under occupation and the Frankish Emperor dead, the fast-acting Emperor Atticus I bypassed multiple traditions surrounding ascension of the Frankish crown to become the Frankish Emperor. The Byzantines and Franks led the Second Battle of Aachen three weeks later.
The damage to the city of Aachen was severe. With parts of the city burned, including the Palace of Aachen, the areas went unused for some time. The Palace of Aachen, highly damaged in the battle, was renovated to become Palatine Cathedral, which still stands today.