Battle of the Winwaed
The death of Penda and the rise of Oswiu to dominance had a major impact in 7th century England. Athelwald was either killed or went into exile. From this time Oswiu became the bretwalda or overlord over all the southern English people including Mercia. Mercia was then divided. North of the River Trent was controlled directly by Oswiu. He made Peada of Mercia, Penda's son, king over the part of Mercia south of the Trent. Peada had married Oswiu's daughter, Alflaed. Peada was murdered five months later by Alflaed, possibly on Oswiu's orders. Mercians rebelled against Oswiu and Peada's brother Wulfhere became king of Mercia.