The Munakata family
The Shimbaru-Nuyama tumuli (kofun) were built for important members of the Munakata family. The earliest written texts that mention the Munakata family are the Kojiki (712) and Nihon shoki (720) and the Shinsen shojiroku, a genealogical record completed in 815, but there is evidence that they came to prominence much earlier. The fulfilment of religious duties appears to have been an important element of state formation and governance from the early Yamato period (300–710), with the court assigning key religious roles to specific families in outlying regions. The Munakata family presided over rituals on Okinoshima on behalf of the court, but they are thought to have fulfilled another crucial role as protectors of key trade routes.
The area that the Munakata family governed in northwestern Kyushu covered the shortest route between Japan and Korea (across the Genkai Sea), and a sea route between Kyushu and the main island of Honshu, where the Yamato heartland was located. By the seventh century, members of the Munakata family simultaneously held the hereditary titles of district administrator and high priest, and records show there was also intermarriage between daughters of the Munakata family and emperors, solidifying their status. After the rituals on Okinoshima ended, the Munakata family remained as high priests of the shrines at Okitsu-miya, Nakatsu-miya and Hetsu-miya. The family line ended abruptly with the death of the last male member, Munakata Ujisada, in 1586, but the name lives on in the area.
