(Japanese: "white barrier"), in Japanese history, office of chief councillor or regent to an adult emperor. The post was created in the Heian period (794-1185) and was thereafter customarily held by members of the Fujiwara clan. Officially serving on behalf of the emperor, regents often acted as the real centre of authority in the government. Fujiwara Mototsune was the first to hold the title of kampaku, in 887, initiating a long period of Fujiwara control over the court which reached its peak in the 11th century under Fujiwara Michinaga. The Fujiwara were able to maintain their hold on the post of kampaku by their extensive and continuing intermarriage with the imperial line. The political power of the kampaku declined after about 1068 with the initiation of the system of rule by retired emperors.
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