Records of heads of state
Officially, the current Emperor of Japan, Akihito is the 125th in line from the first emperor Jimmu, who is variously believed to have reigned in the 1st or 7th century BC. The earliest documentary evidence is only for the 29th emperor, Kinmei (AD 509–571); however, this is sufficient such that even the most conservative of estimates still places the Japanese imperial family as among the oldest lines in the world today.
Emperor Yōzei
Yōzei was succeeded by his father's uncle, Emperor Kōkō; and in the reign of Kōkō's son, Emperor Uda, the madness re-visited the tormented former emperor:Yōzei lived in retirement until the age of 80.
The actual site of Yōzei's grave is known. This emperor is traditionally venerated at a memorial Shinto shrine ("misasagi") at Kyoto.