Eagles of the Crissaegrim

After the return of Morgoth to Middle-earth, the Great Eagles of Beleriand at first made their eyries among the towers of Thangorodrim above Morgoth's fortress of Angband. From there, their Lord Thorondor led them as they watched over the Dark Lord, while the Noldor besieged Angband for centuries. When Morgoth broke the Siege of Angband in the Dagor Bragollach, the Eagles withdrew before the Dark Lord's growing power.¹

For their new abode, they built their eyries far southward of Thangorodrim, among the spires and crags of the Crissaegrim. These sheer peaks formed a part of the Echoriath, the Encircling Mountains that surrounded the hidden vale of Tumladen where the city of Gondolin stood concealed from the outer world. Thorondor and his Eagles had great friendship with the Elves of Gondolin, guarding their Hidden City and spying out foes who approached too closely.

The Crissaegrim lay in the southern part of the Encircling Mountains, and this is perhaps why the Eagles' watch ultimately failed. By treachery, Morgoth discovered the place where Gondolin lay, and brought a force over the high mountains to the north, far from the eyries of the Eagles. That force reached Gondolin and overcame its defences, destroying the last great stronghold of the Elves in Beleriand. Many were lost on that day, but the Eagles played a part in ensuring that at least some survived the city's fall. As a band of survivors made their way out through the mountains, Thorondor and his Eagles drove back their pursuing Orcs and cast them from the mountains, so that the last survivors of Gondolin were able to make a secret escape.

It is unclear whether Thorondor and his Eagles remained among the Crissaegrim after the Fall of Gondolin. They would later take part in the great battles of the War of Wrath, so they must have maintained their eyries somewhere in Beleriand, and they might well have remained among the inaccessible crags of the Crissaegrim even after Gondolin's fall. In the War of Wrath, the world was changed and the mountains of the Crissaegrim were drowned by the Sea, and at this time those Great Eagles that remained flew on eastward to nest among high mountains elsewhere in Middle-earth.