Emperor Seiwa

  • Reign: 858-876
  • Japanese: 清和天皇 (Seiwa tennou)

Emperor Seiwa is known chiefly as the ancestor of the Seiwa Genji, the most prominent, powerful, and historically significant branch of the Minamoto clan.

Seiwa succeeded his father Emperor Montoku as emperor. His grandfather Fujiwara no Yoshifusa served as regent (sesshô) for a time.[1]

Seiwa was a devout Buddhist, and granted the title of Hôin Yamato jôi ("Yamato Upper Rank Seal of the Law") to Kûkai.[2]

Seiwa had six sons who bore the surname Minamoto - a name granted as an honor by the Imperial court. The Seiwa Genji - including first Kamakura shogun Minamoto no Yoritomo and his brother, the famous Minamoto no Yoshitsune - claimed descent from Seiwa's sixth son, Minamoto no Sadazumi, through Sadazumi's son Minamoto no Tsunemoto.

Seiwa was succeeded by one of his sons, who took the throne as Emperor Yôzei.

Preceded by
Emperor Montoku
Emperor of Japan
Succeeded by
Emperor Yôzei


  • Karl Friday, Samurai Warfare and the State in Early Medieval Japan, Routledge (2004), 9.