For all us Silmarillion fans, we win again! :) https://en.wikipedia.org/wiki/E%C3%A4rendil_and_Elwing

"Tolkien took Eärendil's name from the Old English name Earendel, found in the poem Crist 1, which hailed him as "brightest of angels"; this was the beginning of Tolkien's Middle-earth mythology."