Emperor of Japan
Currently, the Emperor of Japan is the only head of state in the world with the English title of "Emperor". The Imperial House of Japan is the oldest continuing monarchical house in the world. The historical origins of the Emperors lie in the late Kofun period of the 3rd–7th centuries AD, but according to the traditional account of the "Kojiki" (finished 712) and "Nihon Shoki" (finished 720), Japan was founded in 660 BC by Emperor Jimmu, who was said to be a direct descendant of the sun-goddess Amaterasu. The current Emperor is Akihito. He acceded to the Chrysanthemum Throne upon the death of his father, Emperor Shōwa (Hirohito), in 1989. The Japanese government announced in December 2017 that Akihito will abdicate on 30 April 2019.
Emperor of Japan
The role of the Emperor of Japan has historically alternated between a largely ceremonial symbolic role and that of an actual imperial ruler. Since the establishment of the first shogunate in 1199, the Emperors of Japan have rarely taken on a role as supreme battlefield commander, unlike many Western monarchs. Japanese Emperors have nearly always been controlled by external political forces, to varying degrees. In fact, between 1192 and 1867, the "shōguns", or their "shikken" regents in Kamakura (1203–1333), were the "de facto" rulers of Japan, although they were nominally appointed by the Emperor. After the Meiji Restoration in 1867, the Emperor was the embodiment of all sovereign power in the realm, as enshrined in the Meiji Constitution of 1889. Since the enactment of the 1947 Constitution, he has been a ceremonial head of state without even nominal political powers.