Emperor Kōshō
, also known as was the fifth legendary emperor of Japan, according to the traditional order of succession. Very little is known about this Emperor due to a lack of material available for further verification and study. Kōshō is known as a "legendary emperor" among historians as his actual existence is disputed. Nothing exists in the "Kojiki" other than his name and genealogy. Kōshō's reign allegedly began in 475 BC, he had one wife and two sons. After his death in 393 BC, his second son supposedly became the next emperor. Legendary narrative. In the "Kojiki" and "Nihon  Shoki", only his name and genealogy were recorded. The Japanese have traditionally accepted this sovereign's historical existence, and an Imperial "misasagi" or tomb for Kōshō is currently maintained; however, no extant contemporary records have been discovered that confirm a view that this historical figure actually reigned. Kōshō is believed to be the oldest son of Emperor Itoku, and his wife Amanotoyototsu-hime. His mother was the daughter of Okishimimi-no-kami. The "Kojiki" records that he ruled from the palace of at Waki-no-kami in what would come to be known as Yamato Province. Kōshō allegedly had a  wife named "Yosotarashi-hime", and fathered two children with her. His reign lasted from 475 BC until his death in 393 BC, his second son then took the throne and would later be referred to as Emperor Kōan. Known information. The existence of at least the first nine Emperors is disputed due to insufficient material available for further verification and study. "Kōshō" is thus regarded by historians as a "legendary Emperor", and is considered to have been the fourth of eight Emperors without specific legends associated with them. The name Kōshō"-tennō" was assigned to him posthumously by later generations, and  literally means "filial manifestation". His name might have been regularized centuries after the lifetime ascribed to Kōshō, possibly during the time in which legends about the origins of the Yamato dynasty were compiled as the chronicles known today as the "Kojiki". While the actual site of Kōshō's grave is not known, the Emperor is traditionally venerated at a memorial Shinto shrine ("misasagi") in Gose. The Imperial Household Agency designates this location as Kōshō's mausoleum. It is formally named "Waki-no-kami no Hakata no yama no e no misasagi". There is a possibility that this figure could have  lived instead in the 1st century (AD), however more research is needed to make any further conclusions. The first emperor that historians state might have actually existed is Emperor Sujin, the 10th emperor of Japan. Outside of the Kojiki, the reign of Emperor Kinmei ( – 571 AD) is the first for which contemporary historiography is able to assign verifiable dates. The conventionally accepted names and dates of the early Emperors were not confirmed as "traditional" though, until the reign of Emperor Kanmu between 737 and 806 AD. Further reading.