" is the first installment in the fantasy trilogy
"The Deed of Paksenarrion
" by US author Elizabeth Moon
Considering the title, you would expect another standard "poor boy/girl becomes prince/hero/wizard" fantasy novel, but thankfully Moon avoids this trap by quickly moving her heroine Paksenarrion (or Paks for short) from humble beginnings to enlistment in a mercenary company.
Paks runs away from home to avoid the arranged marriage that her father set up, and enlists in the mercenary army of Duke Phelan. A large part of this novel gives a semi-realistic portrayal of the life of a grunt in a medieval army - including weapon drills, digging jacks, and the thrill of the first battle. Meanwhile, the fantasy world starts to flesh out with its own geography, history and mythology. The novel finishes with a satisfying conflict that will want you to get part 2 of "The Deed of Paksenarrion" as soon as you can.
If you enjoy good fantasy, you will probably enjoy this novel. If you enjoyed "Ash: A Secret History" by Mary Gentle and "The Black Company" by Glen Cook, you absolutely have to buy this book.