Former Nine Years' War participant Abe clan
The Zenkunen War (前九年の役, Zenkunen no Eki), also known in English as the Former Nine Years' War or the Early Nine Years' War, was fought between the Imperial Court and the Abe clan in Mutsu Province, in Northeast Japan, from 1051 to 1063. It resulted in Imperial Court victory and the surrender of Abe no Sadato. 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.Background
While most provinces were overseen by just a Governor, Mutsu, in what is now the Tohoku region, had a military general in charge of controlling the Emishi natives, who had been subjugated when the Japanese took over the area in the ninth century. Historically, this post was always held by a member of the Abe clan, and there were many conflicts between the Abe general and the Governor over administrative control of the province.
In 1050, the general overseeing the Ainu was Abe no Yoritoki, who levied taxes and confiscated property on his own, rarely paying any heed to the wishes of the province's Governor. The Governor sent word to the capital in Kyoto asking for help, and as a result Minamoto no Yoriyoshi was appointed both Governor and commander-in-chief over controlling the natives. He was sent with his son Yoshiie, then age fifteen, to stop Abe.