The History of Middle-earth
After Tolkien's death, his Arthurian poem would come to be one of the longest-awaited unedited works of his. According to John D. Rateliff, Rayner Unwin had announced plans to edit the poem as early as 1985, but the edition was postponed in favour of "more pressing projects" (such as "The History of Middle-earth" edited 1983–1996), answering the demand for background on Tolkien's legendarium more than his literary production in other areas.