Advice on Writing Alternate Histories

Alternate histories are one of my favorite genres of fiction. I've been enjoying them ever since reading stories by Poul Anderson, Andre Norton, and the master, H. Beam Piper, when I was a teenager.

I've known Michael Skeet almost as long and he's written a few. I was an advance reader for Dixie's Land, which he's published, along with it's sequel, High Risk, on his blog. He also has two published novels, A Poisoned Prayer and A Tangled Weave, which are alternate history fantasies.

He's just published a blog post with some advice for aspiring writers of alternate history stories. It's worth reading, even if you aren't an aspiring novelist, as it might give you an idea why some stories just don't work.

It's a cascade issue, pure and simple. Each change I introduce, while world-building, increases the likelihood of other changes. Which in turn increase the likelihood of—well, you get the idea. In order to try to make the alternate history backdrop still recognizable to readers (which, I'll argue, is one of the primary appeals of—and hence goals of—the genre) the author has to willfully ignore this cascade effect.

The problem I have with this is that it's just too artificial. Yes, alternate history is at some level an artistic con job. But that doesn't mean it has to be obvious. And if you posit a Roman Empire that has survived for 1500 years longer than the real thing did (I'm talking about the Empire in the west here) and yet in terms of its basic structure it hasn't changed at all in that period... well, let's just say that the history of government and administration just about everywhere else disagrees with you.