796. On Offa's death, Kent becomes independent
Eadberht Præn succeeds to Kent
Æthelheard, Archbishop of Canterbury, flees Kent
Eadberht Præn's accession to Kent in 796 is recorded in the Anglo-Saxon Chronicle, and also by the coins bearing Eadberht's name struck at Canterbury in this period (see Grierson and Blackburn, p.283). It is probable that Eadberht of Kent, like Ecgberht of Wessex was another of the exiles sheltered at Charlemagne's court: in a letter to Offa written in 796 (EHD 197), Charlemagne mentions an Eadberht (using the Frankish form Odberht) who had taken refuge with him.
Archbishop Æthelheard's flight is mentioned in a surviving letter of Alcuin (EHD 203), which refers to an earlier letter of Æthelheard in which he said that the clerics of Canterbury asked him to leave. Alcuin nonetheless chastises Æthelheard for deserting his post, reminding him that Archbishop Laurence, faced with the hostile King Eadbald back in 616, stayed put. It may be though that Æthelheard, as the archbishop who helped diminish the primacy of Canterbury by collaborating in the elevation of Lichfield, was concerned to draw Kentish anger away from the cathedral. Nicholas Brooks has suggested that the absence of Christ Church documents before 798, compared with the profusion afterwards, might be attributed to an attack on Æthelheard in newly-independent Canterbury (Brooks, p.121). In any event, another letter of Alcuin (Allott, no. 50), written in 797, imploring the people of Kent to take back their archbishop, makes it clear that they did not want him back.
S. Allott, Alcuin of York, c. A.D. 732 to 804 -- His Life and Letters (York: 1974)
N. Brooks, The Early History of the Church of Canterbury (Leicester: 1984)