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 Go-Komatsu
He is officially considered to have been the Northern pretender from May 24, 1382 to October 21, 1392, when upon Emperor Go-Kameyama's abdication, Go-Komatsu is understood to have been a legitimate emperor (the 100th sovereign) from that date. In 1392, following the post"-Nanboku-chō" unification of the two formerly contending courts, the Southern Emperor Emperor Go-Kameyama reached an agreement with Go-Komatsu to alternate control of the throne between the Northern and Southern courts on a ten-year plan which effectively signaled the end of the southern court's claims to sovereignty. However, Go-Komatsu reneged, not only ruling for 20 years until his own abdication on October 5, 1412, but was succeeded by his own son, rather than by one from the former Southern Court. According to pre-Meiji scholars, Go-Komatsu's reign as a legitimate emperor spanned the years from 1392 through 1412. The present Japanese Imperial Family is descended from the Northern Court emperors.