Fujiwara princes initially served as highest ministers of the imperial Court ("kampaku") and regents ("sesshō") for underage monarchs. The Fujiwara were the proverbial "power behind the throne" for centuries. Apparently they never aspired to supplant the imperial dynasty. Instead, the clan's influence stemmed from its matrimonial alliances with the imperial family. Because consorts of crown princes, younger sons, and emperors were generally Fujiwara women, the male heads of the Fujiwara house were often the father-in-law, brother-in-law, uncle, or maternal grandfather of the emperor. The family reached the peak of its power under Fujiwara no Michinaga (966–1027). He was the grandfather of three emperors, the father of six empresses or imperial consorts, and the grandfather of seven additional imperial consorts; it is no exaggeration to say that it was Michinaga who ruled Japan during this period, not the titular Emperors. As a result of these unusually strong familial links, Michinaga never took the title of Kampaku - he held more than the power that the position would bring, and had no need of the title.