 Cynethryth is associated with her husband in charters and is said to have been a patron of Chertsey Abbey.Pope Adrian I, when elevating Higbert's Bishopric of Lichfield to an Archbishopric, wrote to Offa and Cynethryth jointly.Æthelberht II, King of East Anglia (died 20 May 794) – who was later canonised as Saint Ethelbert the King – is widely believed to have been assassinated, on Offa's orders.