The Vikings established Danelaw over much of the eastern and northern part of England with its boundary roughly stretching from London to Chester. It was an area of political and geographical control imposed by the Viking incursions which was formally agreed to by the Danish warlord, Guthrum and west-Saxon king, Alfred the Great in 886 AD. The Anglo-Saxon Chronicle recorded that London was "refounded" by Alfred the Great in 886. Archaeological research shows that this involved abandonment of Lundenwic and a revival of life and trade within the old Roman walls. London then grew slowly until about 950, after which activity increased dramatically.
What was the name of the eventual capital  of the island nation now ruled by Elizabeth II that helped formed the demarcation of an area of that nation that was held under Danish rule?
London