Seiwa's mother was the daughter of Fujiwara no Yoshifusa (藤原良房), who was regent and great minister of the council of state.

[4] He was the younger half-brother of Imperial Prince Koretaka (惟喬親王; 844–897) Before his ascension to the Chrysanthemum Throne, his personal name (his imina)[5] was Korehito (惟仁),[6] the first member of the Imperial house to be personally named "-hito" 仁.

[1] The emperor is traditionally venerated at the misasagi memorial shrine in the Ukyō-ku ward of Kyoto.

[18][19] Kugyō (公卿) is a collective term for the very few most powerful men attached to the court of the Emperor of Japan in pre-Meiji eras.

[6] [24] Unless otherwise noted (as BC), years are in CE / AD  * Imperial Consort and Regent Empress Jingū is not traditionally listed.