I just realized that I don't entirely know how to classify this book. Some of the reviews I've read have called Ellen Kushner the Georgette Heyer of fantasy. While I can see the Heyer comparison, this seemed more historical than fantasy. Except that the location was made up. Hrm.
Amusing story filled with plotting aristocracy, noble swordsmen, a lot of drunks and thieves, and a practically side-by-side comparison of the court of the nobles and "villains," who are often nobler than the aristocrats. I'll probably have to read the sequels.