This is a great series! Follows Paksenarrion Dorthansdotter, a young provincial woman who joins a mercenary company at 18 and goes on to become a famous knight. Book One is about her days as a mercenary soldier. I was amazed at how detailed Moon's accounts of military life are. In some ways, this book is a little like "By the Sword" by Mercedes Lackey, but I would rate this by far as the better of the two. Paks is good, but not cocky, like Lackey's Kerowyn tends to be. She enjoys just being a common soldier, although her superiors notice something special about her from the first. Eventually, Paks becomes a key player in the main battle of the story, as several mercenary armies ally together to bring down Count Siniava, the bad guy.
At times, "rich in detail" can become just "confusing", especially since (at least in the version I own) Moon spends a great deal of time on the importance of geography, but doesn't include a map. But if you enjoy more sword than sorcery, with likable (and perhaps even more important, believable!) characters, this is a great book.