From the back of the book:
Fighters and clerics have long been mainstays in many AD&D game campaigns. Now, take a look inside this book and discover the dozens of kits created to adapt these basic classes to the unique and popular lands of Faerun. Learn what difference your homeland makes when you choose a warrior's kit, or discover the benefits as a disadvantages or worshiping certain gods of the Realms. Some differences among people are subtle, while others can be quite glaring. The tome reveals ways to identify whether a mercenary hails from Chondath or Waterdeep. It tells you that not all black-clad priests are evil followers Cyric, and even priests of the demipowers have skills to respect.
In addition to priest and warrior kits, unique PC subclasses are revealed herein:
-the Harper
-the Crusader