- Political instability: In the late 9th century, the Frankish Empire was in a state of political turmoil. The empire had been divided between the sons of Charlemagne, and there was constant conflict between the different factions. This instability made it difficult for the Franks to defend their territory from outside attacks.
- Economic opportunity: The Vikings were attracted to Paris by its wealth and prosperity. The city was a major trading center, and it was home to a number of wealthy churches and monasteries. The Vikings hoped to plunder the city and take its riches back to Scandinavia.
- Revenge: The Vikings had been raiding the Frankish coast for several years, and they were angry at the Franks for trying to stop them. They saw the attack on Paris as a way to get revenge for these attacks.
- Religious fervor: Some of the Vikings were motivated by religious fervor. They believed that it was their duty to spread the word of Odin, the Norse god of war. They saw the attack on Paris as a way to convert the Franks to their religion.
The Vikings' attack on Paris was a major event in European history. It was the first time that a Viking army had ever captured a major city. The attack shocked the Franks and forced them to reconsider their defenses against the Vikings. It also led to increased cooperation between the different Frankish factions, which eventually helped to stabilize the empire.