In the middle of the first century, 倭奴国, which is thought to have been located in northern Kyushu (the coast of Hakata Bay), paid tribute to the Later Han Dynasty ("Gokanjo" (Historical records of the Later Han Dynasty)), which is thought to indicate that Wajin political groups in Northern Kyushu were consolidated and 倭奴国 sent an envoy to the Later Han Dynasty as the representative.
1世紀中葉になると北部九州（博多湾沿岸）にあったとされる倭奴国が後漢へ朝貢している（『後漢書』）が、これは北部九州における倭人の政治集団の統合が進み、その代表として倭奴国が後漢へ遣使したと考えられている。