The game is set in the Three Kingdoms period in China and is based on the novel Romance of the Three Kingdoms. Unlike its two immediate predecessors, Sangokushi IX always casts the player as a ruler. The player's goal is to bring every city on the map under his or her command; this is achieved by hiring other historical figures from the book, referred to as officers, and using them to cultivate cities, recruit armies, and fight or plot against enemy forces.