保元の乱
The was a short civil war between rival subjects of the cloistered Emperor Go-Shirakawa of Japan in 1160 fought in order to resolve a dispute about political power. It was preceded by the Hōgen Rebellion in 1156. "Heiji no ran" is seen as a direct outcome of the earlier armed dispute; but unlike "Hōgen no ran," which was a dispute between members of the same clan, this was rather a struggle for power between two rival clans. It is also seen as a precursor of a broader civil war.