What is the name of the fictional book that supposedly records the history of the Hobbits in The Lord of the Rings?

The Red Book of Westmarch is the fictional book that supposedly records the history of the Hobbits in The Lord of the Rings.

Within Tolkien’s framing device, Bilbo Baggins begins the record, Frodo Baggins adds a substantial account of the War of the Ring, and Samwise Gamgee continues and preserves the work. The manuscript is associated with the red-covered volume kept in Hobbiton and later carried into the wider history of Middle-earth.

The Red Book is important because it presents the narrative as a translated historical record rather than as an unexplained modern story. Tolkien sometimes presents himself as a translator of material derived from this imagined source, especially in the appendices and related notes.

It is distinct from the Book of Mazarbul, a record found in Moria. The Red Book also should not be confused with the many separate poems, chronicles, and lore texts mentioned elsewhere in Tolkien’s legendarium.