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Political model

The first of two main components to the political model is the external "pull" factor, which suggests that the weak political bodies of Britain and Western Europe made for an attractive target for Viking raiders. The reasons for these weaknesses vary, but generally can be simplified into decentralised polities, or religious sites. As a result, Viking raiders found it easy to sack and then retreat from these areas which were thus frequently raided. The second case is the internal "push" factor, which coincides with a period just before the Viking Age in which Scandinavia was undergoing a mass centralisation of power in the modern-day countries of Denmark, Sweden, and especially Norway. This centralization of power forced hundreds of chieftains from their lands, which were slowly being eaten up by the kings and dynasties that began to emerge. As a result, many of these chiefs sought refuge elsewhere, and began harrying the coasts of the British Isles and Western Europe. Anders Winroth argues that purposeful choices by warlords "propelled the Viking Age movement of people from Scandinavia."

These models constitute much of what is known about the motivations for and the causes of the Viking Age. In all likelihood, the beginning of this age was the result of some combination of the aforementioned hypotheses.

The Viking colonisation of islands in the North Atlantic has in part been attributed to a period of favourable climate (the Medieval Climactic Optimum), as the weather was relatively stable and predictable, with calm seas. Sea ice was rare, harvests were typically strong, and fishing conditions were good.