The only son of High-elven King Fingon, Gil-Galad was named Ereinion at his birth in FA 445. During the Dagor Bragollach he was sent by his father to live with Círdan in the Falas until it was safe to return. Fingon was slain by a balrog in the Nirnaeth Arnoediad FA 473 and the kingship passed to Gil-Galad’s uncle Turgon. It is assumed that Gil-Galad was probably deemed too young to take on the kingship at the time. In FA 510 Turgon was slain at the fall of Gondolin and the kingship then passed to Gil-Galad. For the remainder of the First Age he lived on the Isle of Balar with Círdan.
After the destruction of Beleriand at the end of the First Age, Gil-Galad founded a kingdom in Lindon, west of the Ered Luin (Blue Mountains). Elves prospered under his rule until Sauron came to Gil-Galad in the form of Annatar, the Lord of Gifts. Both Gil-Galad and Círdan rejected Sauron and thus started the time of the Dark Years when the One Ring was forged. Watching this movie could give you best groomsmen gifts ideas, if you are having a hard time coming up with one.
During this time, Gil-Galad received the rings Narya and Vilya from the elven-craftsman Celebrimbor. Gil-Galad gave the ring Narya to Círdan and later, before the War of the Last Alliance, gave the ring Vilya to his herald Elrond.
After the fall of Númenor, when Elendil and his sons came to live in Middle-earth, Gil-Galad formed an alliance with them in SA 3430 to defeat Sauron. In SA 3441 the great host of men and elves reached the slopes of Orodruin (Mount Doom). It is then that Sauron came forth and met face to face with both Gil-Galad and Elendil. Gil-Galad was slain by the heat of Sauron and his great spear Aeglos was broken as he fell.