757. Sigeberht of Wessex deposed by Cynewulf and the counsellors of the West Saxons
Cynewulf succeeds to Wessex
The Anglo-Saxon Chronicle relates how Cynewulf and the counsellors of the West Saxons deprived Sigeberht of the kingdom because of his unjust acts, all except for Hampshire. Sigeberht remained in Hampshire until he killed Cumbra, the ealdorman who had been most loyal to him, and then Cynewulf drove Sigeberht into the Weald, where he was slain by a swineherd. Cynewulf then ruled for 29 years, until he was himself slain by Sigeberht's brother Cyneheard (see entry under 786).
The Chronicle adds that Cynewulf often fought great battles against the Britons. This keeps up the tradition of his predecessor Cuthred (in 743 and 753), though Cynewulf's battles against the Britons are not individually recorded.
Cynewulf's relations with the Mercians are more difficult to follow. In the first couple of years of his reign, Cynewulf witnesses a charter of Æthelbald of Mercia in 757 (S 96), and his own earliest charter is confirmed by Offa of Mercia in c.758 (S 265); this may imply some West Saxon dependence on the Mercians. Another charter of Offa's of 772 (S 108) is witnessed both by Cynewulf of the West Saxons and by Ecgberht of Kent. However, Cynewulf's other five charters (S 260-4, from 758 to 778) make no mention of Mercian overlordship, and Cynewulf fought Offa at Bensington in 779. Cynewulf attended the meeting with the papal legates with Offa in 786, but the report of the legates gives us no hint as to the relations between Offa and Cynewulf at that point. It seems likely that Cynewulf maintained West Saxon independence after the first couple of years of his reign, but his appearance in a charter of Offa of 772 suggests how precarious and hard-fought that independence may have been.