The prior "bretwalda", Ceawlin, is recorded by the "Anglo-Saxon Chronicle" as having fought Æthelberht in 568. The entry states that Æthelberht lost the battle and was driven back to Kent. The dating of the entries concerning the West Saxons in this section of the "Chronicle" is thought to be unreliable and a recent analysis suggests that Ceawlin's reign is more likely to have been approximately 581–588, rather than the dates of 560–592 that are given in the "Chronicle". The battle was at "Wibbandun", which may be translated as Wibba's Mount; it is not known where this was.