 Almost no documentary sources exist about the history of the kingdom before the reign of Rædwald, who reigned until about 624.Sources of information include the names of a few of the early Wuffing kings, mentioned in a short passage in Bede's "Ecclesiastical History of the English People", written in the 730s.In 616, Rædwald defeated and killed Æthelfrith of Northumbria in the Battle of the River Idle and then installed Edwin as the new Deiran king.