After Demeter1's excellent writeup above, I will just have to dispense with any plot synopsis of Guy Gavriel Kay's 1990 novel about a whole nation annihilated for revenge. I still find I must say something:
Read this story.
* * * * *
I have read much of Guy Gavriel Kay's other work: The Fionavar Tapestry, A Song for Arbonne, The Lions of Al-Rassan, The Sarantine Mosaic. These are all very, very good, and you should read them. But Tigana towers over all. A now-deleted writeup called it "The best single Fantasy novel I've ever read" and it's difficult to disagree with that.
Melancholy and regret effuse the entire narrative: sorrow for things taken away and regret for opportunities lost. But so do outrage and determination: Outrage at the atrocities committed, and determination to undo them, at least to some small degree.
The characters are well-drawn, specifically because they fit into the world around themselves. These are not cardboard cutouts. These are not spoiled suburban teenagers on a trip to the mall. Their motiviations and actions are directed by who they are, how they were brought up, and what has happened to them in their lives. The mythology religion of the Palm is described in just enough detail as to give the characters their extra dimensions without making them hapless toys of Fate (such as happened in, say, The Silmarillion).
I have to disagree with Demeter slightly, since it's clear who the heroes are, and who the villains are. Things appear more complicated because Kay makes us cry for the villains and the motivations that caused them to perform their villainy at the same time he makes us cry for the plight of Lower Corte, and the awful events the heroes engineer to secure a brighter future.
Kay has a magnificent way of setting the reader up and surprising him or her: he will entrap you in some fascinating history of the Palm, or an anecdote relating to the Palm's mythology, or admiring the scenery, when suddenly things are happening. He makes you feel that you should have seen it coming while you were admiring the scenery. It's your fault for not paying attention3. Maybe it's a plot device, but it works, again, and again.
Of course Lower Corte gets its own name back by the end of the story; you should have guessed that already. Tigana has so much more between its front and back covers that you will never regret the 24 hours or so it will take you to read it, probably all in one sitting.
1Does she have flowing, sea-green hair, I wonder?
2Primarily the young Asoli singer Devin, from whose viewpoint most of the story is told.
3By the way, dog-ear or otherwise mark the page with the little prophetic folk-poem when you come to it; you will need it later.