Yesterday I read the author's introduction to a historical mystery and immediately put the book down. I had no intention of wasting my time any further.

To my way of thinking a historical differs from an alternate history or a pure fantasy in that it does not play too fast and loose with history. There is a lot of play in the historical record anyway. For example, the author noted that she had changed the date of one event, as given by chroniclers, because there existed some dispute about the date's accuracy. Fair enough. Mary and I will take advantage of ambiguities in the record and arguments amongst historians to choose the interpretation that suits our purpose.

However, the author went on to admit that she had moved a famous fire -- whose date was well documented -- back eight years to the time of her story. That I could not accept.

We've begun work on our ninth Byzantine mystery which takes place in 548, the year of Empress Theodora's death. Plenty of interesting events happened that year and we intend to take advantage of them. We would never consider, however, moving the plague of 542 to 548 because it would make a good story.

Imagine if authors started doing that. If you can move a fire back eight years to suit why not move the attack on Pearl Harbor back to Black Friday? Maybe the Hindenberg could crash on the same day the Titanic sank. What if John Kennedy was assassinated during the Cuban missile crisis?

I suppose shuffling historical events into conjunction makes for a sort of alternate history. I haven't read enough to know if it's done. Maybe it is a new subgenre. If so Mary and I should start a new series. How about Justinian, the last Roman emperor in the west fights off the barbarians and aided by his great general Belisarius averts the fall of Rome? It would be a lot easier.