Why did the Vikings attack?

By Peter Konieczny

The Introduction to the Medieval Warfare issue on the Viking invasion of Europe:

At the dawn of the ninth century, communities throughout western Europe faced “sudden and unforeseen attacks of the Northmen.” Pirates and plunderers came from the sea and struck the unprotected, killing or capturing all those they could get their hands on. What made the Vikings explode out of Denmark and Norway around the year 800?

Perhaps the earliest explanation – besides the chronicles which explained the attacks as God’s punishment for unspecified sins – comes from Dudo of St. Quentin. In the early eleventh century he penned a book about the history of the dukes of Normandy, who were originally Vikings, and spent a few paragraphs talking about how barbarian peoples were prone to having too many children. Dudo goes on to write:


When these have grown up, they clamor fiercely against their fathers and their grandfathers, or more frequently against each other, for shares of property; and, as they are over-many, and the land they inhabit is not large enough for them to live, there is a very old custom by which a multitude of youths is selected by lot and expelled into the realms of other nations, to win kingdoms for themselves by fighting, where they can live in uninterrupted peace.

Historians have generally been dismissive of this explanation, citing the fact that when the Vikings began their attacks in the late eighth century they simply plundered territories and returned home. It would be at least a couple of generations before Viking armies set out to conquer lands they could settle in.

Twelfth-century image of Danes about to invade England. – Pierpont Morgan Library MS M.736 fol. 9v

Many theories

Economic reasons have been one of the most cited factors in explaining the Viking age. This period saw increased trade and money becoming more important in northern Europe, and the Norse peoples were eager to gain wealth and began to use violent means to procure it. One interesting explanation, put forth by Mary Valante, states that it was the demand for slaves in the Middle East and Byzantium that gave impetus to the raiding. The Vikings often targeted monasteries where they would capture many young men and boys – a very valuable commodity because of their education and literacy. Once castrated, these males would be the ideal eunuchs, serving in a Caliph’s harem or in an imperial bureaucracy.

Another recent theory by Steve Ashby suggests that the desire for wealth was only part of the reason for the attacks. For those Vikings taking part, it would be a chance for them to show their courage and skill in front of their peers, and gain what we might call ‘street cred’. It is interesting to note that, while the Vikings plundered Christian artefacts, they often kept them intact instead of melting them down – perhaps as way of offering proof of their victories. As Ashby explains, “the lure of the raid was thus more than booty; it was about winning and preserving power through the enchantment of travel and the doing of deeds. This provides an important correction to models that focus on the need for portable wealth; the act of acquiring silver was as important as the silver itself.”

Other explanations revolve around various environmental or technological factors. For instance, the navigation and shipbuilding skills of the Vikings grew rapidly at this time, allowing them to travel across oceans or up rivers. Some historians believed that once the Vikings obtained their maritime superiority, they were eager to use it to pursue warfare and raiding, a practice already common among other European peoples.

The role of religion

It has also been suggested that the Norse religion may have predisposed its people to be greater risk-takers. Neil Price offers this idea:


We are left with a sobering conclusion, which is that the Vikings created one of the few known world mythologies to include the pre-ordained and permanent ruin of all creation and all the powers that shaped it, with no lasting afterlife for anyone at all. The cosmos began in the frozen emptiness of Ginnungagap, and will end in fire with the last battle. Everything will burn at the Ragnarok, whatever gods and humans may do. The outcome of our actions, our fate, is already decided and therefore does not matter. What is important is the manner of our conduct as we go to meet it. The psychological implications of this and other aspects of the Norse ‘religion’ bear thinking about.

For those who had such a worldview, the idea of undertaking risky voyages across the sea and living a life of battle and plunder would have been very appealing.

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Religion was also an important factor in another recent explanation of why the Vikings attacked, but in this case it was a reaction to the approach of Christianity. The second half of the eighth century saw the Carolingians, particularly under Charlemagne, using military means to force Christianity upon their pagan neighbours. The Saxons would suffer under repeated attacks from the Carolingians, with their religious symbols being destroyed and massacres of their peoples taking place. These events would have been well-known to the Norse people living in Scandinavia, and they could have reacted by deciding to pre-emptively strike against the Carolingians and the Church. However, other scholars have pointed out that the Vikings do not seem to have been politically united enough to carry out such a broad war.


Finally, one of the most recent explanations for the Viking phenomenon is related to what Dudo of St. Quentin suggested. The Norse practised polygamy and concubinage, which meant that some men would have several women, while others would have none. This competition between men would have motivated the single men to leave Scandinavia in search of wealth, captives and fame, which they could use to gain their own wives and concubines.

These are just some of the theories behind the rise of the Vikings. It might be that it was a combination of several factors that convinced them that a life of raiding and plundering was a good choice. Whatever the reason, the emergence of the Vikings would unleash a new era on Western Europe.

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