 An article on the historicity of the Icelandic sagas notes that " Brodir " is not a Norse proper name at all , and is itself derived from the Irish name variously written as <unk> , <unk> or <unk> . According to the article , the name first appears in the Annals of Ulster in the year 853 , when a <unk> of south @-@ east Ireland named <unk> mac <unk> was involved in the murder of a rival before being slain himself . The name only appears in Norse context twice — at the Battle of Clontarf , and in 1160 for the King of Dublin , <unk> son of <unk> — and had a longer circulation in Irish literature . The same article also suggests that while there is no doubt about the historical truth of the Battle of Clontarf , the name " <unk> " , along with other names in the Njál 's saga account of the Clontarf episode , may have been borrowed from the Landnámabók . 
