Toumakoku (投馬国, Toumakoku/Tsumakoku) is one of the countries said to have existed in the Japanese archipelago in the 3rd century.
[1] It is listed in the Wajinden[2][3] and the ruling official is called a Mimi [ja; simple][2][1] According to "Records of Three Kingdoms," Toumakoku was located 20 days by water to the south from Fumi (in Umi, Kasuya District) or Sueranokuni (Karatsu City, Saga Prefecture).
[1] Hata District (central-western part of the Korean Peninsula)).
It may have been the leading power of the Wakoku.
[3]