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Thorin Oakenshield
Thorin Oakenshield was the King under the Mountain and leader of the company of dwarves that sought to reclaim the Lonely Mountain from the dragon Smaug.
Thorin Oakenshield was a prince of the line of Durin and the son of Thrain II. Following the destruction of Erebor by the dragon Smaug, Thorin lived in exile in the Blue Mountains. He eventually led a company of thirteen dwarves, accompanied by the hobbit Bilbo Baggins and the wizard Gandalf the Grey, on a quest to reclaim their ancestral home and the vast treasure hoard held within.
The Battle of Five Armies
Upon reaching the Lonely Mountain, the company succeeded in driving out the dragon, but Thorin succumbed to dragon-sickness, a deep greed for the Arkenstone. This led to a tense standoff with the Men of Lake-town and the Elves of Mirkwood. However, the arrival of common enemies forced an alliance, and Thorin died heroically in the Battle of Five Armies. His legacy was remembered by later figures in the history of Middle-earth, including Gimli, who served alongside Aragorn, Frodo Baggins, Legolas Greenleaf, Meriadoc Brandybuck, Peregrin Took, and Samwise Gamgee during the War of the Ring.