Ereinion

Ereinion, better known as Gil-galad, was a high Elven lord, and son of Fingon. After the death of Turgon he ascended to become the High King of the kingdom of Noldor.

With the emergence of Sauron, Ereinion joined forces with the human king Elendil to defeat the forces spreading from Mordor. Their large and well-trained combined forces engaged Sauron's multiple times.

Ereinion was killed in battle, along with Elendil, at the end of the war, during the Battle of Gladden Fields.

Source: "The Silmarillion", by J. R. R. Tolkien