In An Unexpected Journey, Baggins attempts to reclaim the lost Dwarf Kingdom of Erebor from Smaug, the dragon.

BBC: First instalment of The Hobbit to get Royal premiere

We soon learn about the dwarven kingdom of Erebor, a.k.a The Lonely Mountain, and Thror, its King Under the Mountain.

FORBES: Review: The Hobbit: An Unexpected, But Very Welcome, Journey