Oswiu was the brother of Oswald and succeeded him after the latter's defeat in Maserfield. Oswiu succeeded where Edwin and Oswald failed as, in 655, he slew Penda during the Battle of the Winwaed, making him the first Northumbrian King also to control the kingdom of Mercia. During his reign, he presided over the Synod of Whitby, an attempt to reconcile religious differences between Roman and Celtic Christianity, in which he eventually backed Rome. Oswiu died from illness in 670 and divided Deira and Bernicia between two of his sons. IV.5 His son Aldfrith of Northumbria took over the throne upon his death.
Oswiu was the brother of Oswald and succeeded him after the latter's defeat in Maserfield. Oswiu succeeded where Edwin and Oswald failed as, in 655, he slew Penda during the Battle of the Winwaed, making him the first Northumbrian King also to control the kingdom of Mercia. During his reign, he presided over the Synod of Whitby, an attempt to reconcile religious differences between Roman and Celtic Christianity, in which he eventually backed Rome. Oswiu died from illness in 670 and divided Deira and Bernicia between two of his sons. IV.5 His son Aldfrith of Northumbria took over the throne upon his death.