Mordor is the region of Middle-earth in which Middle-earth: Shadow of Mordor and Middle-earth: Shadow of War take place. It is the home kingdom of Sauron, situated in southeastern Middle-earth and east of Gondor, and Ithilien and the great river. Mordor was chosen to be Sauron's fortress because of the mountain ranges surrounding it on three sides, creating a natural fortress against his enemies. Much of the land was a volcanic waste due to the activity of Mount Doom, but the regions that remained unaffected by the volcanic eruptions were lush with wildlife and forests, allowing the Dark Lord's slaves to raise food for his armies here. Eventually the landscape was sapped of all resources due to the large army Sauron had kept in Mordor.
Mordor is protected by three mountain ranges on all sides. The Ash Mountains lie in the north and the Mountains of Shadow in the west and south. The only viable large entryway into Mordor lies in the north-west corner of Mordor: the deep valley of Udûn protected by the Black Gate of Mordor. Sauron's Dark Tower, the fortress of Barad-dûr, was located at the foothill of the Ash Mountains.
The plateau of Gorgoroth lies to the south-west of Barad-dûr, and so does Mount Doom; to the east lies the plains of Lithlad. Mordor was protected from attacks on all fronts because of its unscalable mountains, while the arid lands of Gorgoroth and Núrn caused great attrition to armies that did manage to break through, preventing them from staying there for a prolonged period of time.
Núrn, in the southern part of Mordor, was more fertile and sufficiently moist to house the inland sea of Núrnen. The land was somewhat fertile due to the ashes from Mount Doom, allowing dry-land farming.
The narrow land of Ithilien with the city of Osigiliath lies to the west of Mordor. Directly east lies Rhûn, the Eastlands, and to the west lies Khand.
The east of Mordor is not mentioned often in descriptions of Mordor. What is known is that the east was a heavily defended area containing a border of forts facing towards Sauron's allies in Rhun.
First & Second Age
Sauron chose to settle in Mordor one thousand years after the First Age ended, and it remained his kingdom for the entirety of the Second and Third Ages of Middle-earth. Sauron had used Mount Doom to forge his One Ring, and at the foot of Mount Doom he built his stronghold Barad-dûr.
What became Mordor was the area around Cuvienen, the Lake of Awakening, where the Elves originated; the great earthquakes caused by the Valar's attack on Utumno, and later the destruction of Beleriand, emptied the lake except for the Nurnen. Doubtless Sauron was amused by the idea of setting up his headquarters where some of his greatest enemies originated
Sauron ruled Mordor for more than two and a half thousand years. After he obtained the One Ring, he launched an attack from Mordor upon the Elves of Eregion. This attack was fought off by the Númenóreans. Almost thousand years later he fought the Men again. He was then captured by the Númenóreans and taken to their island kingdom (which eventually caused their demise) after which Sauron returned to Mordor.
After Sauron's attempt to overthrow the Men and Elves failed he was fought back into Mordor. After a siege which lasted for several years, the Last Alliance of Elves and Men entered Mordor and defeated Sauron in a final battle at Mount Doom. Gondor then took upon them the task to guard Mordor and to prevent any evil forces from leaving it. Minas Ithil, the Towers of the Teeth and the Tower of Cirith Ungol were built to watch the two major entrances to Mordor.
Sauron managed to use Wainriders to weaken Gondor and used his Nazgûl to reclaim the lands of Arnor, where he started rebuilding his armies. The Nazgûl also managed to capture and corrupt Minas Ithil, a city on the border of Mordor. Sauron returned to Mordor after his false defeat in Dol Guldur (which took place during the events of The Hobbit), and Mordor became too powerful to be captured by any army in Middle-earth.
The Last Alliance
During the War of the Ring, Sauron assembled all his forces in Mordor. After the Battle of Pelennor Fields, the army of the West marched to the Black Gate. Sauron sent out his armies to crush the combined forces of the Men of Gondor and Rohan. However, Frodo Baggins managed to destroy the One Ring causing Sauron's demise and Mordor's fall. Barad-dur exploded and the Black Gate and the Towers of Teeth collapsed. Mount Doom erupted, and Sauron's Nazgûl were destroyed.
Mordor became empty once more, and the Uruk inside were killed. The lands of Mordor were given to both Gondor's enemies out of sympathy as well as the freed slaves of Núrn whom Sauron had forced to farm in Núrn to feed his armies.
- Mordor actually has two meanings: the Black Land or the Dark Land in Tolkien's fictional language Sindarin, and The Land of Shadow in Quenya.
- A proposed etymology out of the context of Middle-earth is Old English mrthor, which means "mortal sin" or "murder."
- Mordor is also a name cited in some Nordic mythologies referring to a land where its citizens practice evil without knowing it, imposed on themselves by the society long created for that purpose.