Vilya

Elvish cosmology includes various layers of 'airs'; an Outer region that enfolded the World, an Upper region that was the province of the stars, and a Lower region, nearest the Earth. The root vil- in 'Vilya' properly refers only to this third, lower region.

Confusingly, though Vilya is unequivocally called the mightiest of the Three Rings, Nenya the White Ring is elsewhere (in The History of Galadriel and Celeborn in Unfinished Tales) called the chief of the Three. This appears to be a contradiction, but it can be seen as implying that Nenya held some kind of authority over the other two Rings (perhaps something like the authority of the Ruling Ring) while Vilya was the Ring containing the most natural power.

Gil-galad's actions in granting Vilya to Elrond are difficult to explain. Celebrimbor had sent Vilya and Narya north hoping to keep them safe and secret, far out of Sauron's hands, but Gil-galad chose to send one of the Rings back into an Eriador now overrun by the Dark Lord's forces. This dangerous action might have been more explicable if Elrond could have made use of Vilya in the war, but he could not; Sauron still wore the One Ring, so any attempt to draw on the Blue Ring's power was unthinkable.

The only apparent explanation for Gil-galad's choice seems to be that it was founded in either foresight or hope. If he was looking forward to a time when Sauron's authority over the Rings would be lost, then his granting of Vilya to Elrond makes becomes a little more understandable. Nearly two thousand years later, after the War of the Last Alliance and the loss of the One Ring, Gil-galad's hope was fulfilled, and Elrond was able to tap Vilya's power to make Rivendell a haven and a place of peace among the troubles of Middle-earth.