The local magistrate of the the has given you an imperial charter: go north into the monster-ridden borderlands of Shenmen, and subdue the area. The lands you claim will be yours and your descendents’ until the end of time, as a vassal province of Lingshen. King Huang himself signed the decree!
The game will open with a brief introduction with a functionary (Kui Xing) and the official order to pacify the savage frontier of Shenmen. You don’t need to know each other before, although such connections could be useful (and exploitable) in the game.