While this book is competent historical fiction, it is NOT (as it stands by itself) alternate history. The story is broken up into three sections (43-70 AD Emperor Claudius; 122-138 AD, Emperor Hadrian; 314-337 AD, Emperor Constantine), where various characters in Roman Britain* deal with the effects of a prophecy, probably sent from the future (but never explained). And, by ‘deal with’ I mean attempt to take advantage of future knowledge with varying degrees of success. However, history isn’t really changed, and, by the epilogue (set in 418 AD), things are pretty much as we know them. I imagine that things may be explained in later novels (this is series of four) and historical events may or may not be altered – although, based on the blurbs on the back of books 2-4, possibly not much. This either feels like the author is doing a REALLY LONG setup for an alternate history series (like, seriously, an entire initial novel with no alternate history?), in which case, bold move; or this is just a Mitchner-esque historical epic using the prophecy as a plot hook. Either way, I’m not sure that I’m feeling it. It’s not that the book is bad, it’s just not as advertised. Very low 3 stars. I may revisit the series later (The second book, CONQUERER, appears to deal with medieval Britain - Vikings, the Norman Conquest, etc.) but not right now.