When Oswald became the first Christian king of Northumbria he sought the aid of the monks of Iona, the disciples of Columba, for the conversion of the Saxons of the North.
A monk called Aidan was sent by the community of Iona to assist Oswald in the summer of 635. He gave Aidan the island of Lindisfarne adjoining his own royal fortress of Bamborough, for his monastery.
In 642 there was war between Oswald and Penda, the pagan King of Mercia, and, on 5th August, Oswald was defeated, killed and dismembered by Penda in a fierce battle at a place called Maserfelth which today is known today as Oswestry or Croesoswallt (Oswald’s Cross) in Welsh. Nearby is Oswald’s well which marks the place where a great bird let the right arm from the dismembered body fall and where a healing spring appeared.
The relics of Saint Oswald were recovered and enshrined in Saint Oswald’s Priory, Gloucester, but that perished at the Dissolution. Saint Oswald’s head was finally buried with Saint Cuthbert whose shrine is now in Durham Cathedral. When St Cuthbert’s shrine was opened in the 19th century the head of St Oswald was found to be present.