Viking invasions

Viking expansion is the process by which the Vikings sailed most of the North Atlantic, reaching south to North Africa and east to Russia, Constantinople and the Middle East as looters, traders, colonists and mercenaries. Vikings under Leif Ericsson, the heir to Erik the Red, reached North America and set up a short-lived settlement in present-day L'Anse aux Meadows, Newfoundland and Labrador, Canada. Longer and more established settlements were formed in Greenland, Iceland, Great Britain and Normandy.

There is much debate among historians about what drove the Viking expansion. One widely held idea is that it was a quest for retaliation against continental Europeans for their previous invasions of Viking homelands, such as Charlemagne's campaign to force Scandinavian pagans to convert to Christianity by killing any who refused to become baptized. The historian Rudolf Simek has observed, "It is not a coincidence if the early Viking activity occurred during the reign of Charlemagne." Those who favor this explanation point out that the penetration of Christianity into Scandinavia caused serious conflict and divided Norway for almost a century. However, the first target of Viking raids was not the Frankish Kingdom, but Christian monasteries in England, which seems inconsistent with vengeance as a motive but would be consistent with religious warfare.

Another idea is that the Viking population had exceeded the agricultural potential of their homeland. This may have been true of western Norway, where there were few reserves of land, but it is unlikely the rest of Scandinavia was experiencing famine.

Alternatively, some scholars propose that the Viking expansion was driven by a youth bulge effect: since the eldest son of a family customarily inherited the family's entire estate, younger sons had to seek their fortune by emigrating or engaging in raids. Peter Sawyer suggests that most Vikings emigrated due the attractiveness of owning more land rather than the necessity of having it.

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