For nearly five-hundred years they lived in peace and prosperity trusting in the secrecy of their hidden city and refusing to take part in the affairs and Battles of the Beleriand, save for the Nirnaeth Arnoediad (Battle of Unnumbered Tears) where fortunately for them, the secret of Gondolin was preserved thanks to the bravery of the Men of Dor-lómin. However, their secret would not remain a secret for long as others such as Húrin were used in finding its location, and then later from a threat from within.
It was Maeglin, son of Eöl who bitterly resented the fact that he could not win the affection of the woman he desired and jealous of the one who did, betrayed the people of Gondolin after being captured by Morgoth. This led to the Fall of Gondolin and the near destruction of its people; however, a group of them were saved by Tuor and Idril and the bravery of Glorfindel.
The remaining Gondolindrim fled to the Havens of Sirion where they mourned greatly for the loss of their great city. There they lived in peace under the lordship of Tuor and Idril and later their son Eärendil until the deadly attack on the refuge by the Sons of Fëanor who were seeking the recovery of the Silmaril. Most all there were slain and if any did survive they probably went over the sea to Valinor.
Gondolindrim was a Sindarin word that meant 'Gondolin-people'.
- The Silmarillion pgs. 138, 159 & 192
- Unfinished Tales: Of Tuor and his Coming to Gondolin pgs. 31-2 & 42
- The Complete Guide to Middle-earth
- The Atlas of Middle-earth pgs. 22-3