Battle_of_Brunanburh The Battle of Brunanburh was an English victory in 937 by the army of Æthelstan, King of England, and his brother, Edmund, over the combined armies of Olaf III Guthfrithson, Norse-Gael King of Dublin, Constantine II, King of Scots, and Owen I, King of Strathclyde. Mention is also made in some sources of Irish, Welsh and Cornish mercenaries.