During the mid-15th to early 17th Century, often known as the Sengoku period, Japan saw continuous warfare between the Daimyo – the great feudal lords – as they strove for power and domination. Daimyo is a mass battle wargame set during this Sengoku period. As Daimyo, players will take control of a clan, assemble an army, and crush their enemies in order to unite Japan under their banner. The core of the game is based around your army, which is made up of units and groups of units known as contingents, with unit characteristics determined by varying dice types. Players' commanders also play a role in the battle, with a variety of abilities that can turn the tide of an encounter. Also included in this rulebook are a number of scenarios with varying themes and objectives as well as a robust, yet simple to play, map-based campaign system allowing players to decide the fate of Japan.