King under the Mountain

King under the Mountain was the title taken by Thráin I, founder of the Dwarf-kingdom of Lonely Mountain, and maintained by those Kings of Durin's folk who dwelt there. The line was broken twice, once by Thorin I (he and four generations of his descendants ruled from the Grey Mountains, not Lonely Mountain), and once by the Dragon Smaug (who claimed the title for himself). In both cases, the line was restored to a rightful heir.

The Line of Kings under the Mountain

1. Thráin I
2. Thorin I – abandoned the Kingdom for the Grey Mountains
3. Thrór – restored the Kingdom but lost it to Smaug
4. Thorin II Oakenshield – regained the Kingdom
5. Dáin II Ironfoot
6. Thorin III Stonehelm