Five kings of Wa

The five kings of Wa (倭の五王, Wa no go ō) are kings of ancient Japan who sent envoys to China during the 5th century to strengthen the legitimacy of their claims to power by gaining the recognition of the Chinese emperor. Details about them are unknown. According to written records in China, their names were San (讃), Chin (珍), Sai (濟), Kō (興) and Bu (武).

479 and 502 was automatic rank up by the establishment of new dynasty of China.

These titles for the military Sovereignly over the countries had no actual powers. The appointments reflected the struggle for hegemony over the region between Goguryeo and Wa, depicted in the Gwanggaeto Stele.

As the name of kings recorded in Chinese history are very different from the names of emperors in the Nihonshoki, the specification of which emperor was the one recorded is the subject of numerous disputes which have endured for centuries. Most contemporary historians assign the five Japanese kings to the following emperors (two possibilities are identified for Kings San and Chin), mostly based on the individual features of their genealogies reported in the Chinese sources. On the other hand, archeological evidence, such as the inscriptions on the Inariyama and Eta Funayama Sword, also supports the idea that Bu is an equivalent of Emperor Yūryaku, who was called Wakatakeru Ōkimi by his contemporaries.

Since Bu is most likely to be Yūryaku, Kō, who is said to be Bu's older brother, is likely to be an equivalent of Ankō, who is also noted in the Nihonshoki as an elder brother to Yūryaku. However, the Book of Song records Kō as "Crown Prince Kō"; there is a possibility that he is not Ankō, but rather Prince Kinashi no Karu, who was a crown prince of Ingyō.

Some suspect that both were rulers of a non-Yamato court which in the 5th century ruled most of what is today Japan, and who were eventually ruined by the ancestors of the current imperial dynasty. However, such an idea is not widely accepted among scholars.

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