In 2799 TA, the Battle of Azanulbizar was fought in Middle Earth between the Dwarves under Thrain II and the Orcs under Azog during the War of the Dwarves and Orcs.
Why did it happen?
After the sack of Erebor and Dale by Smaug the Dragon in 2770 TA, King Thror and his son Thrain II fled south and wandered for many years before settling in Dunland. In 2790 TA, after giving Thrain the last of the Seven Dwarven Rings, Thror went north through the Redhorn Pass with Nar and came to the valley of Azanulbizar where he was killed by the Orc, Azog. When Nar brought word to Thrain of his father’s death, Thrain sought revenge and sent messengers north, east, and west to gather a large army of Dwarves to wage war upon the Orcs of the Misty Mountains. After three years, with all his forces assembled, Thrain declared war upon the Orcs and over the next six years, fought the Orcs underneath the Misty Mountains, sacking Orc strongholds from Mount Gundabad to the Gladden Fields. By 2799 TA, all the remaining Orcs had gathered in Moria where the Dwarves met them at Azanulbizar outside the East Gate.
Who was involved?
The Dwarven army at Azanulbizar is estimated to have numbered around 6,000 Dwarves from the Seven Houses: Longbeards, Firebeards, Broadbeams, Blacklocks, Stonefoots, Ironfists, and Stiffbeards. Of this number, 5,000 were led by Thrain II and his son, Thorin Oakenshield, while 1,000 were reinforcements led by Nain and his son Dain Ironfoot from the Iron Hills. The Orc army at Azanulbizar numbered an estimated 15,000 Orcs, of which 10,000 were positioned outside the East Gate of Moria while 5,000 were arrayed on the western slope of the Misty Mountains.
What happened?
The battle opened with Thrain II leading the Dwarven vanguard against the Orc host, only to be repulsed and driven into the woods next to Kheled-Zaram. In the fighting, Thrain and his son Thorin were wounded while Frerin and Fundin were slain. Elsewhere, the fighting between the Dwarves and Orcs was evenly matched until reinforcements arrived under Nain and Dain Ironfoot, which tipped the battle in favour of the Dwarves. Nain and his forces cut their way through the ranks of Orcs to engage Azog and his bodyguard in front of the East Gate of Moria, only for Nain to be slain by Azog. At that point, the Orc army began to rout with the right-wing fleeing south along the valley with the Dwarven army in pursuit. Azog, with all his bodyguard slain, then fled toward the East Gate of Moria. As Azog climbed the steps to the gate, however, Dain Ironfoot pursued him and reached him at the door where he slew him and hewed off his head, thereby winning the battle. While the Dwarves lost half of their army in the battle, 3,000 killed or wounded, the Orcs suffered 10,000 casualties.
What changed as a result?
The Battle of Azanulbizar was a pyrrhic victory for the Dwarves. In the aftermath of the battle, the Dwarves stripped all their dead’s weapons and armour before burning the bodies on a pyre. The Dwarves then dispersed back to their homelands with Dain Ironfoot returning to the Iron Hills while Thrain and Thorin returned to Dunland. In 2802 TA, Thrain and Thorin moved to Ered Luin in Eriador where they prospered, and the number of Dwarves increased steadily over the years. In 2841 TA, Thrain sought to reclaim Erebor and left Ered Luin with a small company of Dwarves, only to be captured by the forces of Sauron and imprisoned in Dol Guldur four years later. Thrain died in 2850 TA and the task of reclaiming Erebor would fall to his son, Thorin Oakenshield.
Bibliography
Fisher, Mark. “Battle of Azanulbizar.” The Encyclopaedia of Arda. Last revised January 21, 2014. https://www.glyphweb.com/arda/b/battleofazanulbizar.php
Tolkien, J.R.R. The Lord of the Rings: The Return of the King. London, Harper Collins Publishers, 2004.
Tolkien, J.R.R. & Tolkien, Christopher. The History of Middle Earth: The Peoples of Middle Earth. London, Allen and Unwin, 1996.