During the following years Northumbria repeatedly changed hands between the English kings and the Norwegian invaders, but was definitively brought under English control by Eadred in 954, completing the unification of England. At about this time, Lothian, bordering the northern portion of Northumbria (Bernicia), was ceded to the Kingdom of Scotland. On 12 July 927 the monarchs of Britain gathered at Eamont in Cumbria to recognise Æthelstan as king of the English. This can be considered England's 'foundation date', although the process of unification had taken almost 100 years.