20,000? 200,000? 2,000,000? Essentially I'm asking how many vikings actually came to Britain. Would they have been overwhelmed in terms of shear numbers by Anglo Saxons and Celts?
Also, when did the Norse language cease to be spoken in the Danelaw area?
While much can always be said, I summarized some basic points as well as the links to the relevant posts before in: How did life/culture differ in Danelaw compared to life in its neighbors of Wessex, Mercia and Northumbria?
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The current academic consensus apparently amounts to "thousands (a few thousands)" of Scandinavian settlers, rather than ten thousands or more (Hadley 2006: 130).
On the other hand, I'm not so sure about the estimated population of (northern and eastern) England around 900 CE, as well as its growth rate during late Anglo-Saxon period. Our most reliable departure point, Domesday Book, record about 270,000 people (villeins, cottars and so on, as a head of the household) in countryside and 20,000 people in urban settings, and researchers surmise from these figures that about 1.3 million to 1.5 million of people lived in whole England in 1086 (Dyer 2002: 94).
If we assume the total population of later Danelaw as about 300,000 (this is clearly very underestimated figure) and the number of Scandinavian settlers as 9,000 (it is also highly likely to be overestimated), the very rough ratio of the settlers among the population would be 3%, and it is likely that the actual ratio would be further lower as a whole.
If their settlements had some regional concentrations, as sometimes suggested, however, it is likely that thousands of the settlers (mostly elites) left undeniable trace on some local communities as well as culture.
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