In The Hobbit, he and 12 other Dwarves visited Bilbo Baggins on Gandalf's advice to hire him as a burglar, to steal back their treasure from the dragon Smaug. He especially wanted the Arkenstone, and was furious when Bilbo stole it to use as a bargaining counter with the Elvenkingking, who also laid claim to the treasure. The conflict was averted by an attack of Goblins and Wargs, and the Dwarves joined forces with the Elves and the great eagles to defeat them in what came to be called the Battle of the Five Armies. During the battle Thorin was mortally wounded, but before he died he made his peace with Bilbo.
His dying words were, "If more of us valued food and cheer and song above hoarded gold, it would be a merrier world."