Which 1937 J.R.R. Tolkien book introduces Bilbo Baggins?

The 1937 J.R.R. Tolkien book that introduces Bilbo Baggins is The Hobbit. Its full title is The Hobbit, or There and Back Again, and it follows Bilbo from a quiet life in Hobbiton into an adventure involving dwarves, a dragon, and a powerful ring.

Tolkien wrote The Hobbit before The Lord of the Rings. The story began, famously, with a sentence Tolkien wrote while marking examination papers: “In a hole in the ground there lived a hobbit.” The book’s tone is generally lighter and more children’s-literature-oriented than Tolkien’s later epic.

Bilbo’s encounter with Gollum and the One Ring became especially important when Tolkien expanded the mythology in The Lord of the Rings. Later editions altered some details of the riddle-game chapter so that the ring’s history would fit the developing story. The book was published by George Allen & Unwin in London in 1937.