In the early Heian period, he served as Seii Taishogun and suppressed many Emishi in the Tohoku region. He founded Kiyomizu-dera in Kyoto. He was a man of such sincerity and magnanimity that when the enemy general Aterui surrendered, he pleaded with the Imperial Court to spare his life rather than execute him.

He built the golden age of the Fujiwara clan by making his daughters consorts to the Emperor, practicing regency politics. He composed the 'Full Moon Poem.' 'This world, I think, is indeed my world. For the full moon, I see, has no flaw.' He composed this with the feeling that there was nothing in this world that did not go his way. A strategist and a man of quick wit.

Praised as a child prodigy from a young age, he became a Monjo Hakase, the highest rank for a scholar. He rose to the position of Minister of the Right as a politician. He also foresaw the decline of the Tang Dynasty and the dangers of sea voyages, proposing the abolition of envoys to Tang China.