Reading history is a bit like reading fantasy or sci-fi; it’s just that the fanfic of history is generally more consistent than that of fantasy. I have been reading history lately (Victoria and Disraeli by Theo Aronson, the last couple of days, to be precise; history about personal relationships) and it is the story that I enjoy most of all. I don’t mean this particular story, but rather the way in which historical writing is concerned with constructing this great, rich, world, where all things can be infinitely detailed (indeed, in one’s imagination they are so) and linked. It’s similar in fantasy novels, and any body of work that grows up around some central world or story. Marion Zimmer Bradley’s Darkover stories, for example, or the Dune saga and associated fanfic — it’s all about completing missing bits of the story, trying to fit things together. The composite story, written by many minds and many sources.
This aspect of history has really got nothing to do with the fact that the world described ‘actually existed’ — although that’s a benefit insofar as consistency between works is concerned. There is a great deal of satisfaction to be had in reading about some ‘alternative world’, from different authors; whether it is ‘real’ or not is, in a way, irrelevant. I just like that process of building up the feeling of knowing a world, real and historical or otherwise.