became The Lord of the Rings. He renewed work on The Silmarillion after completing The Lord of the Rings, and he greatly desired to publish the two works together. When it became clear that would not be possible, Tolkien turned his full attention to preparing The Lord of the Rings for publication. Tolkien wished to make the mythology more believable by bringing it into line with the Round World version of the creation story. He was persuaded not to do this in 1946; later attempts conflicted with the already published texts of The Hobbit and The Lord of the Rings. In the late 1950s, Tolkien returned to The Silmarillion, working mostly with the theological and philosophical underpinnings of the work rather than with the narratives. By this time, he had doubts about fundamental aspects of the work that went back to the earliest versions of the stories, and it seems that he felt the need to resolve these problems before he could attempt a "final" version. During this time he wrote extensively on such topics as the nature of evil in Arda, the origin of Orcs, the customs of the Elves, the nature and means of Elvish rebirth, the flat world and the story of the Sun and Moon. In any event, with one or two exceptions, he wrought little change to the narratives during the remaining years of his life. Posthumous publication For several years after his father's death, Christopher Tolkien worked on a Silmarillion narrative. He tried to use the latest writings of his father's and to keep as much internal consistency (and consistency with The Lord of the Rings) as possible, given the many conflicting drafts. He enlisted the help of the Canadian Guy Gavriel Kay, now the author of a fantasy trilogy inspired by Arthurian legend; Kay spent a year with him in Oxford editing the materials in secret. As explained in The History of Middle-earth, Christopher Tolkien drew upon numerous sources, relying on post-Lord of the Rings works where possible, ultimately reaching as far back as the 1917 Book of Lost Tales to fill in portions of the narrative that his father had planned to write but never addressed. In one later chapter of Quenta Silmarillion, "Of the Ruin of Doriath", untouched since the early 1930s, he had to construct a narrative practically from scratch. Christopher Tolkien commented that, had he taken more time and