However, since the era of Emperor Heijo, FUJIWARA no Fuyutsugu (who had won the confidence of Emperor Saga) had rapidly gained power and started to overwhelm other families when the Southern House lost its power after the Iyo Shinno no Hen (Conspiracy of Imperial Prince Iyo) of 807, and the Ceremonial House lost its power after the Kusuko no Hen Conspiracy of 810.
しかしながら、平城天皇朝以降、大同2年（807年）の伊予親王事件にて南家、弘仁元年（810年）の薬子の変にて式家の勢力が衰えると、嵯峨天皇の信任を得た藤原冬嗣が急速に台頭し他家を圧倒するようになった。