Aethelweard

The Chronicle of Aethelweard was written within living memory of the battle, possible around 975.  He calls the site Brunandun:

In the year in which the very mighty king Æthelstan enjoyed the crown of empire, 926 years were passed from the glorious incarnation of our Saviour. [939 = 937]  After thirteen years a huge battle was fought against the barbarians at Brunandun, wherefore it is still called the ` great battle’ by the common people. Then the barbarian forces were overcome on all sides, and held the superiority no more. Afterwards he [i.e. the king] drove them off from the shores of the ocean, and the Scots and Picts both submitted.  The fields of Britain were consolidated into one, there was peace everywhere, and abundance of all things, and [since then] no fleet has remained here, having advanced against these shores, except under treaty with the English. [941 = 939] After a period of two years Æthelstan, a king worthy of honour, left the world.

(Ed – A Campbell – London 1962)