Gil-galad (Elvish for star of radiance) is known as the last High King of the Noldor in Middle-earth.
Born in Hithlum as Ereinion (meaning descendent of kings), he was sent away at a young age by his father to live with Círdan, the Shipwright after Dagor Bragollach. As one of the few survivors of the attacks on the docks of the Falas, he and Círdan escaped to the Isle named Balar. Here he lived throughout the First Age. After the fall of Gondolin, and the death of Turgon, Gil-galad Ereinian was known as the High king of the Noldor.
At the beginning of the second Age Gil-galad summoned most of the Noldor to live with him under his reign in Forlindon(Northern Lindon), west of the Blue Mountains. Harlindon (South Lindon) was being governed by Celeborn, who left after a while and so the remaining Grey elves joined Gil-galad. The first 1000 years of his reign were peaceful, because Morgoth was defeated and the Elves thought that evil was gone forever. Sauron, however, was planning on taking over Middle-earth and after he betrayed the smiths of Eregion war came on the lands of Middle-earth.
In 1695 The Dark Lord Sauron sent out a massive orc army to conquer Eriador. Gil-galad fought desperatly to turn the tide, and helped Eregion to survive. But Eregion fell in 1697 and just two years later Sauron had conquered Eriador. Before the elves of Lindon were wiped out in a final attack, help came from the edain. Tar-Minastir, the eleventh king of Numenor, sent a large army which drove Sauron away. Sauron would have his revenge for the aid of the men of Numenor in this.
Fall of Gil-galad
After the destruction of Númenór, some of the remaining Númenóreans founded Arnor and Gondor. When Sauron declared war on these realms, the made an alliance with Gil-galad, which is known as the War of the last Alliance. A combined army of the men of the West and the Elves of Gil-galad eventually defeated Sauron after a siege on Barad-dûr for seven years. Against Aeglos, the spear of Gil-galad, none could stand. Gil-galad fell in this battle in a fight with Sauron himself, sharing the fate of Elendil.
Since Gil-galad had no offspring, his death meant the end of the line of The High Kings of the Noldor in Middle-Earth. His Realm Lindon surived the troubles of the Third Age and eventually became the longest existing realm of the Eldar in Middle-Earth. It was eventually abandoned in the Fourth Age. He had been given the Ring of Air by Celebrimbror after the destruction of Eregion, which he passed on to his herald Elrond before he died.