I've read this so many times it's really hard to think about it - the whole story is part of the background for me. Triggered by reading When In the Course- in Federation - now that's an interesting story, with hints of mystery. Actually, it kind of reminds me of the mystery in the Fuzzy stories - how _did_ they get there? Though my viewpoint on that is warped by the Tuning and Mayhar 'sequels'... Yeah. I have a hard time discussing Lord Kalvan because it links with too many other things.
So, that aside - it's the usual story of the outsider coming in (from our universe/time. usually) and changing everything (at least theoretically, for the better). Piper does it nicely, with reasonable reasons for Kalvan to be listened to in the first place, and reasons for him to know what he needs to know to make a difference. And the Paratimers' comments on the whole sequence (and some of his own thoughts - like about beating Napoleon's jump in rank) illuminate the events nicely. The discussion at the end of the book about the Paratime Secret makes Lord Kalvan a major point in the Paratime universe - which is mostly interesting because it was apparently originally written for the Federation universe. Anyway, neat. Excellent characterization - well, it is a Piper. Oh, that reminds me - in this book, and also in When In the Course-, Piper breaks his usual pattern of linear characters - in most of his books, he introduces one character or set of characters at the beginning, and everyone else comes in as they relate to that original set. Here, three different sets of characters are introduced separately, and only after all three are established do the stories begin to braid. Interesting. ( )

This was not my first Piper, nor my second. I was well into reading Piper before discovering this, but wow, what an incredible adventure this started for me. And now with the continuations that Roland Green and John Carr have produced, this Kalvan Canon (That is a Pun) just grows and grows. Much like Hos-Hostigos.

I had long since read L Sprague de Camp, Lest Darkness Falls, the story where a man of our times (and Calvin Morrison is a Pennsylvania State Trooper from the 50's or 60's) returns to another time where the use of the technology from now can change that past they have entered. We see it also in Leo Frankowski's Crosstime Engineer series. We see it often. We see it in the Connecticut Yankee in King Arthur's Court, so we have Twain laying out a format for this 100 years before Piper and those others I have cited.

What we have is the effective use of Pike and Musket, the English Civil War, the Thirty Years War, in an alternate universe centered on Pennsylvania. That is the premise. It works for me. There are not that many pages but within them we have the introduction, the ability to change society, the ability to stabilize a country headed to defeat and turn it around.

Our hero emerges as just that, a hero. Our villains are men who want power. All the elements are there and in under 250 pages we have it all. Battles, derring-do, a little romance. A great romp that I return to again and again. ( )

This is one of my favorite books and I read it every year. It's a great tale of a man misplaced in his origins who accidentally finds himself the key man in a crisis through an accident of fate. Even with every re-read of this book, I find myself gripped by it. Sadly, the author took his own life in despair before this book was published. It was his best-selling work. ( )

Not my favorite of Piper's works...a fairly formulaic Alternate Earth story. ( )

Classic time-traveller, alternate-universes saga as a Pennsylvania state trooper creates a 30 Years War type army on a different timeline. Old but still enjoyable. ( )