Dáin Ironfoot inherits the title King under the Mountain in J.R.R. Tolkien’s The Hobbit. He is Thorin Oakenshield’s cousin and the leader of the Dwarves of the Iron Hills. Dáin brings an armed force to the Lonely Mountain during the conflict that follows Smaug’s death.
Thorin is the claimant who leads the company to Erebor, but he dies after the Battle of the Five Armies. Before his death, Thorin reconciles with Bilbo and recognizes the destructive effects of his possessiveness. The kingship therefore passes to Dáin, who survives the battle and takes responsibility for the restored realm.
Dáin’s title is tied to Erebor, the Lonely Mountain, and the Dwarven kingdom beneath it. Bard becomes the ruler of the rebuilt Dale, while Dáin rules the Dwarves. These separate successions explain why both characters emerge as important leaders after Smaug’s fall without holding the same crown.