Unfinished Tales
As with "The Silmarillion", Christopher Tolkien edited and published "Unfinished Tales" before he had finished his study of the materials in his father's archive. "Unfinished Tales" provides more detailed information about characters, events and places mentioned only briefly in "The Lord of the Rings". Versions of such tales, including the origins of Gandalf and the other Istari (Wizards), the death of Isildur and the loss of the One Ring in the Gladden Fields, and the founding of the kingdom of Rohan, help expand knowledge about Middle-earth.