Our only specific encounter with Elemmakil is at the time that Voronwë led Tuor to Gondolin in the deep winter of I 495. He would have been an inhabitant of Gondolin since its founding in I 116 (and indeed Voronwë confirmed that he knew Elemmakil, even though he had left the city years beforehand). Of his origins before this we can only speculate, though he would probably have dwelt with Turgon's people in Nevrast and (assuming that he descended from the Noldor) he might have originated in the West.

Of Elemmakil's fate we know nothing. As a soldier of Gondolin, he likely perished in that city's fall in I 510. Alternatively, he might conceivably have been among those who escaped the disaster and made their way to the refuges at the Mouths of Sirion but, if so, he is not named as such.

There were both Noldor and Sindar living in Gondolin, and since we're not specifically told which of these people Elemmakil belonged to, he might in principle have belonged to either of them. His high station and especially his Quenya name imply that he was probably one of the Noldor, but this is not stated explicitly, and he might conceivably have originated among the Sindar of Nevrast.