the most powerful of the Fujiwara regents, during whose reign the Imperial capital in Kyōto achieved its greatest splendour, and the Fujiwara family, which dominated the Japanese court between 857 and 1160, reached the apogee of its rule.

Michinaga was the son of Kaneie, the previous head of the Fujiwara family, and he succeeded to the leadership of the clan after the death of his elder brother in 995. Michinaga never took the title kampaku (chancellor) but advanced through the regular Imperial offices until he was named great minister of state (dajō daijin) in 1017.

Michinaga was given the honorary title of Nairan, which allowed him access to the private papers of the palace. The emperor's authority was still acknowledged, but the real seat of the government was transferred from the Imperial palace to Michinaga's administration (mandokoro). Four separate emperors were forced to marry his daughters; two emperors were his blood nephews and three his grandsons.

Some of Japan's greatest literature was produced during Michinaga's dominance. The magnificence of his palace became the subject of many stories. The famous Makura no sōshi (Pillow Book) (“Pillow Book”), by the court lady Sei Shōnagon, contains many references to Michinaga; Prince Genji, the hero of the great Japanese novel Genji monogatari (The Tale of Genji (Tale of Genji, The)), is supposed to be partially modelled on Michinaga.

Conditions in the countryside seriously disintegrated during Michinaga's reign, however, and many powerful warrior families in the provinces refused to acknowledge central control. For a while Michinaga was able to stabilize conditions in the capital by paying warriors of the Minamoto and Taira clans to act as a kind of supplementary police force, but, as the Fujiwaras declined, these bands gradually usurped much of the governmental power.