The , also known in English as the Former Nine Years War or the Early Nine Years War, was fought from 1051 to 1063, in Japan's Mutsu Province, at the far north of the main island of Honshū. Like the other major conflicts of the Heian period, such as the Gosannen War and the Genpei War, the Zenkunen war was a struggle for power within the samurai clans.