See also: alternative history | historical fiction | science fiction
Unreviewed but noteworthy: Richard Adams, Shardik; E.R. Eddison, The Worm Ouroboros; George R.R. Martin, A Song of Ice and Fire (unfinished series); Patricia A. McKillip, The Riddle-Master of Hed; J.R.R. Tolkien, The Lord of the Rings (of course!); Tad Williams, Memory, Sorrow, Thorn; ...