Middle-earth is the fictional region that forms the main setting of J.R.R. Tolkien’s stories, including The Hobbit.
The name translates Tolkien’s use of the Old English term middangeard, which referred to the inhabited world. In Tolkien’s mythology, Middle-earth is not another planet; it is a major region of Arda, the world created for his legendarium, during a remote period of Earth’s imagined history.
The Hobbit and The Lord of the Rings focus on the northwestern part of Middle-earth. Important locations include the Shire, Rivendell, Mirkwood, Rohan, Gondor, Mordor, and the Lonely Mountain. Earlier stories in The Silmarillion describe events in the First Age, especially in Beleriand.
Readers sometimes use “Middle-earth” as if it means the entire setting of every Tolkien story. More precisely, it is one part of Arda. Aman, the Undying Lands west of Middle-earth, is another major region in Tolkien’s world.