Against Three Lands – George Phillies
Angus Valentine McDonald, the youngest son of McDonald Clan’s ruling family, is serving as his father’s regent while the rest of the family is politicking at the capital. He is ordered to travel overseas to determine why trade has been disrupted. He travels with a group of merchants and some guards, one of whom is Nancy Juliet. (No, there’s no pending romance. It would not be considered appropriate.) When they reach Mercia, they learn that it is under attack by several (competing) groups of foreigners.
The reader will quickly recognize the attackers as similar to early-modern Europeans - and Angus’s homeland as similar to Japan of that time. (Giving the protagonists names like Angus Valentine and Nancy Juliet accomplishes two slightly-conflicting purposes. It keeps the reader out of too-well-worn mental ruts, and gives the protagonists names that convey cultural cues that make sense to the reader.) The Lunarian empire is akin to China - which has the resources to deal with the encroaching foreigners, but lacks the political will. The world in which this novel is placed is not quite ours, the Hundred Isles are not quite Japan, and there is a possibility that the protagonists may make a difference.
The cover blurb undersells this book, and makes a highly-nuanced novel look like a cookie-cutter fantasy. It’s not. Angus is not trying to defeat evil foes; he’s trying to survive cut-throat politics. The most important thing to know about Clan McDonald is that the All-Conquering Generalissimo (not quite the Shogun) views it as a potential competitor.
A solidly-good story embedded in subtly-good world-building. The world is enough like ours that to make the reader comfortable - with differences that make the story more interesting.