Oswine, Oswin or Osuine was a King of Deira in northern England.

The Battle of Maserfield, a corruption of the Welsh Maes Elferth was fought on 5 August 641 or 642 between the Anglo-Saxon kings Oswald of Northumbria and Penda of Mercia allied with Welsh Kingdom of Gwynedd, ending in Oswald's defeat, death, and dismemberment. The location was also known as Cogwy in Welsh, with Welshmen from Pengwern participating in the battle, probably as allies of the Mercians. Bede reports the commonly accepted date given above; the Welsh Annales Cambriae is generally considered incorrect in giving the year of the battle as 644. The site of the battle is traditionally identified with Oswestry.