Given the choice, which do you prefer? Real history? Or historical fiction? (Assume, for the purposes of this discussion that they are equally well-written and engaging.)
This is an excellent question, and one I don't think I can answer fully in the parameters given above.
I enjoy reading true history books. I've always found it fascinating to see how different things were in various times and places both near and far to my own. I worked at the library in college, and in my weekly shelving shift, if I was assigned the second floor, I always tried for the D, E and F sections, which are the history portions under the LC classification system. I read a lot of really random books in those four years, and I can definitely say that a great history book is a treasure.
However, it can be hard to find a great history book. There's probably two main reasons this happens. If the primary sources just aren't there, and there's enough speculation involved that it dances over and across the line into historical fiction, I'd hesitate to really consider that history. The other problem is when an academic writer keeps it very academic. I had a much higher tolerance for full-on academic writing when I was in school. These days, as much as I'd like to think I'm reading to expand my mind, a lot of my reading time is really for relaxing. Dry history turns me off like almost nothing else.
This leads me to why I don't believe I can answer today's question within the required parameters. I think historical fiction will always have the edge over history in being well written and engaging because it is fiction. My favorite historical fiction books are the ones where the author has clearly done their research and given the settings and characters an authentic feel. However, I think we all know that all the research in the world does not erase the fact that any author writing about a time period not their own is bringing their own time references into play, and is able to use those to enrich the story. I think using the lens of a more recent time makes the historical fiction more relate-able, and therefore often more enjoyable.
So, I'd like to think I'd prefer history, because I value the lessons of the past, but I have to admit, I'd pick up the historical fiction first, most days.