Judging from the rather limited historical evidence for Scandinavian settlement in the Wirral, the Norse, under the leadsership of Ingimund, were allowed to settle in Mercian territory by permission of Æthelflæd, the Lady of the Mercians, who ruled Mercia from 911 until her death in 918.
According to Wainwright:
The literary details such as those which now envelop the story of the attack on Chester may be set aside as unreliable, but the sequence of events is clear: Norsemen, expelled from Ireland and beaten off from Wales, settled with Æthelflæd’s permission near Chester in Mercian territory. After a period of peaceful settlement the new colonists became aggressive.
Wainwright, F.T., (1975), “Scandinavian England”, Chichester, Phillimore
As Stephen Mathews has pointed out, this would appear to be rather strange behaviour on behalf of a ruler who usually displayed considerable political acumen.
This is especially true when one considers the strategic position occupied by the Wirral – between two majors rivers, the Dee and the Mersey.
Indeed, the only contemporary parallel that springs to mind is when Charles the Simple granted the land by the mouth of the Seine, later to become Normandy, to Rollo in 911. (See here…) In exchange, Rollo promised military support to Charles, which included defending the Seine against Viking attack.
Although this grant of land included the thriving beach market at Meols, David Griffiths has presented good reasons to believe that Meols lay in a political no man’s land and functioned as a tax free zone, so there would be no loss of revenue to Mercia.
(Griffiths, D. “The Maritime Economy of the Chester Region in the Anglo-Saxon Period” in Carrington, P. (ed) (1996) “Where Deva Spreads Her Wizard Stream”, p. 52. )
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