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 Meiji
Since the modern era, deceased Emperors of Japan have been given a posthumous name, which is the name of the era coinciding with the Emperor's time on the throne. Therefore, while publicly known in his lifetime merely as "The Emperor", the Japanese monarch historically known as "Emperor Meiji" obtained his current title in reference to the Meiji period which spanned almost the entirety of his reign. His personal name, which is not used in any formal or official context, except for his signature, was .