After the Roman legions left England and Wales there was at mosty one century before the Germans (or Angles / Saxons) settled in England and the east Lothian of Sxcotland (but not Cumbria)

Then the Norse settled in Yorkshire and the Wash areas of England.

Alfred the Great expanded his kingdom of wessex and Wales started to develop into a distinct linguistic state.

Then the saxon kingdoms reunited for a while, reaching its epoch under the later canonised Edward the Confessor in whose reign the first WestMInster Abbey was built.

His crowned successor Harold managed to defeat the Notse king Harold in 1066 in the North of the realm but got the arrow in the eye at Hastings or to be more specific what is today the ruins of Battle Abbey in Sussex.