Guy Gavriel Kay is one of those authors whose works are always absolutely brilliant. His research is impeccable, his worlds are painstakingly built up and feel real in a way that few authors can manage.
This is, of course, due to Kay's approach towards fantasy, which involves taking a historical period and turning it into a fantasy world that reflects and refracts history.
The other thing I love about Kay is that, while the setting and story is king in his story, his characters are still compelling and work as the hook on which the story can hang.
Though this was not an easy read, it was a well paced, brilliantly executed one. There aren't many writers whose works hold on to me, long after I finish them, the way that Kay's do.