Which of Tolkien’s sons edited and published Unfinished Tales in 1980?

Christopher Tolkien edited and published Unfinished Tales in 1980.

Unfinished Tales of Númenor and Middle-earth is a collection of narratives left incomplete or unpublished by J.R.R. Tolkien. Christopher Tolkien selected, organized, edited, and annotated the material, presenting stories from different periods of Middle-earth’s history. The book was published after The Silmarillion and helped readers explore subjects that received only brief treatment elsewhere.

The collection includes accounts involving Númenor, Gondor, Rohan, the Wizards, and the children of Túrin. Some passages exist in multiple versions or contain unresolved details, so Christopher frequently explained editorial choices in notes and commentary.

Christopher Tolkien was J.R.R. Tolkien’s third son and became the principal editor of his father’s posthumous writings. He also edited the twelve-volume History of Middle-earth series. Unfinished Tales is therefore not a novel completed by J.R.R. Tolkien, but an edited presentation of surviving texts.