Nazgul

According to Tolkien's The Lord of the Rings, the Nazgûl arose as Sauron's most powerful servants in the Second Age of Middle-earth. They were once mortal men; three being "great lords" of Númenor. Sauron gave each of them one of nine Rings of Power. Ultimately, however, they were bound to the One Ring and completely enslaved by the will ofSauron.

The corrupting effect of the rings extended the bearers' earthly lives far beyond their normal lifespans. Some passages in the novel suggest that the Nazgûl wore their rings, while others suggest that Sauron actually held them.

Appearance and characteristics
The Nazgûl wore their rings long enough that their physical forms faded away until they had become entirely invisible to mortal eyes. Their black robes gave them visible form. During the assault on Minas Tirith, the leader of the Nine, the Witch-king of Angmar, cast back his hood to reveal a crown, but the head that wore it was invisible. While wearing the One Ring, Frodo perceived them as pale figures robed in white, with "haggard hands" and wearing crowns.

In The Fellowship of the Ring they were armed with steel swords, while the Witch-king wielded a Morgul blade that could turn its victim into a wraith. During the Battle of the Pelennor Fields, the Witch-king bore a "long pale sword", and later used a mace against Éowyn.

The Witch-king practiced black magic, and used it to break the gates of Minas Tirith. Tolkien said of the Nazgûl ". . . their chief weapon was terror. This was actually greater when they were unclad and invisible; and it was greater also when they were gathered together." They exuded an aura of fear:

Close or prolonged encounters with a Nazgûl caused unconsciousness, nightmares, and eventual death: an effect known as "the Black Breath". Aragorn used the herb athelas to treat victims of the Black Breath, including Frodo, Faramir, Éowyn, and Merry.

History within the legendarium
The Appendices of The Return of the King explain that the Nazgûl first appeared around S.A. 2251, some 700 years after the rings were forged, and were soon established as Sauron's principal servants. They were dispersed after the first overthrow of Sauron in S.A. 3441 at the hands of the Last Alliance of Elves and Men, but their survival was assured since the One Ring survived.

They re-emerged around T.A. 1300, when the Witch-king led Sauron's forces against the successor kingdoms of Arnor: Rhudaur, Cardolan and Arthedain. He effectively destroyed all the successor kingdoms, but was defeated in 1975 and returned to Mordor. There he gathered the other Nazgûl in preparation for the return of Sauron to that realm.

In 2000, the Nazgûl besieged Minas Ithil and, after two years, captured it and acquired its palantír for Sauron. The city thereafter became Minas Morgul, the stronghold of the Nazgûl. Sauron returned to Mordor in 2942 and declared himself openly in 2951. Two or three of the Nazgûl were sent to garrison Dol Guldur, his fortress in Mirkwood.

By 3017, near the beginning of the story told in The Lord of the Rings, Sauron had learned from Gollum that Bilbo Baggins of The Shire had the One Ring in his possession. Sauron entrusted its recovery to the Nazgûl. They reappeared "west of the River", riding black horses that were bred or trained in Mordor to endure their terror. They learned that the Ring had passed to Bilbo's heir, Frodo, and followed him and his companions to Bree. Aragorn arrived ahead of them and hid the Hobbits from their pursuers, but eventually five of the Nazgûl cornered Frodo and his company at Weathertop, where the Witch-king stabbed Frodo in the shoulder with the Morgul blade, breaking off a piece of it in theHobbit's flesh. When all Nine were swept away by the waters of the river Bruinen, their horses were drowned, and the Ringwraiths were forced to return to Mordor to regroup.

In 3018 the nine companions of the Fellowship of the Ring left Rivendell as the "Nine Walkers", in opposition to the Nazgûl, the "Nine Riders". The latter reappeared mounted on hideous flying beasts (reminiscent of — and in part suggested by — pterodactyls). They were then called Winged Nazgûl.

During the Battle of the Pelennor Fields (portrayed in Return of the King), the Witch-king himself was slain by Éowyn and Merry: Merry's surreptitious stroke with an enchantedBarrow-blade drove the Witch-king to his knees, allowing Éowyn, the niece of Théoden, to drive her sword between his crown and mantle. Thus was the Witch-king destroyed by a woman and a Hobbit, fulfilling the prophecy that "not by the hand of man will he fall".[4] Both weapons that pierced him disintegrated, and both assailants were stricken with the Black Breath.

The remaining eight Ringwraiths attacked the Army of the West during the last battle at the Black Gate. When Frodo claimed the Ring for his own near the fires of Mount Doom, Sauron ordered the eight to fly to intercept him. They arrived too late, however: Gollum seized the Ring and fell into the Cracks of Doom, and the Nazgûl perished with its destruction.