Five kings of Wa

The 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).
Chinese records and the bestowed titles on the kings of Wa.
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.
Comparison with the Nihon Shoki.
As the name of kings recorded in Chinese history are very different from the names of Emperors in the "Nihon Shoki", 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 the 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.