Sometime between 878 and 886, the territory was formally ceded by Wessex to the Danelaw kingdom of East Anglia, under the Treaty of Alfred and Guthrum.
Millalgi 878. ja 886. aasta vahel loovutati territoorium Wessexi poolt ametlikult Danelaw East Anglia kuningriigile, vastavalt Alfredi ja Guthrumi lepingule.