Smaug was the dragon who possessed the Lonely Mountain’s treasure in J.R.R. Tolkien’s The Hobbit.
Smaug attacked the Dwarf kingdom of Erebor and drove its people into exile before taking the mountain’s vast hoard. Many years later, Thorin Oakenshield led a company to reclaim Erebor, and Gandalf recruited Bilbo Baggins to join the expedition as its burglar.
Bilbo’s encounter with Smaug is one of the novel’s central episodes. By speaking carefully and using the name “Under-name,” Bilbo learns that Smaug has a vulnerable patch in the armor-like jewels covering his underside. Bilbo later tells Bard of Lake-town about this weakness, helping Bard defeat the dragon with the Black Arrow.
Smaug is distinct from Tolkien’s other dragons. Glaurung and Ancalagon belong primarily to the older First Age stories, while Scatha is a dragon from the history of the North. Smaug’s death ends his occupation of Erebor but does not end the conflict over the treasure.