Penda of Mercia
The Angles strengthened their influence over the area in 628, when (says the "Anglo-Saxon Chronicle") the West Saxons fought (the Anglian) Penda of Mercia at Cirencester and afterwards came to terms. Penda had evidently won, but had probably forged an alliance with local leaders, since the former Dobunnic polity did not immediately become part of Mercia but instead became an allied or client kingdom of the Hwicce.