[3] James E. Fraser suggests that Elfin may be further identified with the Eliuin m. Cuirp whose capture alongside Conamail son of Cano is recorded by the Annals of Ulster under the year 673.
This patronymic, or perhaps gentilic, is attached to the King of the Picts Nechtan nepos Uerb, who may be identifiable with Neithon of Alt Clut and therefore have been Elfin's great-grandfather.
[7] The Annals of Tigernach report that in the year 678, the Dál Riatan kindred known as the Cenél Loairn, under Ferchar Fota, were defeated by the Britons at a location called Tíriu.
If the 673 annal is taken to refer to Elfin he had apparently been active earlier in Dál Riata, in the year in which Domangart, son of Domnall Brecc, king of Cenél nGabráin, was killed.
Elfin may also have led the Britons who defeated the Cruthin of Ulster at Ráth Mór in Mag Line (a plain near modern Larne) in 682, killing their king Cathassach.