Edwin (Old English: Ēadwine; c. 586 – 12 October 632/633), also known as Eadwine or Æduinus, was the King of Deira and Bernicia – which later became known as Northumbria – from around 616 until his death. He was the second monarch to rule both of these northern English kingdoms and the first to convert to Christianity. After he died in battle, he was venerated as a saint.
Edwin was the son of Ælle, the first known king of Deira, and likely had at least two siblings. His sister Acha was married to Æthelfrith, king of neighbouring Bernicia. Edwin was forced into exile when Æthelfrith conquered Deira. His travels took him to the court of Rædwald of East Anglia, who defeated Æthelfrith in 616, allowing Edwin to ascend the thrones of Bernicia and Deira. After the death of his patron Rædwald around 624, Edwin became the most powerful ruler in Britain. Bede the Venerable includes him in his list of kings who exercised imperium over other Anglo-Saxon monarchs, and the Anglo-Saxon Chronicle gives him the title bretwalda, or "ruler of Britain".