Emperor Seiwa

was the 56th emperor of Japan, according to the traditional order of succession. Seiwa's reign started in 858 and ended in 876.
Traditional history.
This prince's personal name ("imina") was before he became the monarch. In the Imperial House of Japan, Korehito was the first to have the suffix "-hito" 仁 in his name.
Korehito was the fourth son of Emperor Montoku. His mother was the daughter of Fujiwara no Yoshifusa (藤原良房), who was regent and great minister of the council of state.
Events of Seiwa's life.
Prince Korehito became emperor at the age of 8, but the real power was held by his grandfather, Yoshifusa.
After his death.
The actual site of Seiwa's grave is known. This emperor is traditionally venerated at a memorial Shinto shrine ("misasagi") at Kyoto. The Imperial Household Agency designates this location as Seiwa's mausoleum. It is formally named "Minooyama no misasagi". From the site of his tomb, he was sometimes referred to as Mizunoo (水尾).
The "kami" of Emperor Seiwa is venerated at Seiwa-tennō-sha in Saga, Yamashiro province.
Eras of reign.
The years of Seiwa's reign are identified by more than one era name or "nengō".