First of all, especially if you live in the USA, this book is MUCH better than it looks. I have seen a US edition which depicts the heroine as a youthful and voluptuous girl in what appears to be chain mail underwear. The edition I own simply has a snowy landscape on the cover, the only figures visible being clad appropriately for the weather.
This book has LOTS in it. There is the clash and death of cultures (focused on more than the military aspect), lots of detail in the characters and societies, gritty and unheroic events and plot, and best of all, distinctly different and most unheroic (in the Hollywood or normal fantasy novel sense) characters.
Yen Olass, the main female character, has had it tough. She most definately could not pass for the bikini babe on the US edition cover. She is stocky, middle aged, tough, and passes for a man for part of the novel. Her homeland has been destroyed, and she has been subjected to appalling treatment by the invading race.
Regret and ashes are a dominant theme.
There is lots more to say, but the book says it better. Read it, it really is good - fantasy, but without the dross you usually have to filter out. Hugh Cook's books showed what was wrong with some of my former favourite fantasy authors, and how much better the genre can be.