According to the article dated Hinoene of September in ca. 252 of "Nihonshoki," Chogo, the king of Paekche, met Nagahiko CHIKUMA, an envoy from Japan, and gave him one seven-pronged sword, one nanatsuko no kagami (a mirror with seven small decoration mirrors), and various other treasures, hoping to form a friendship.
『日本書紀』神功皇后52年（252年?）九月丙子の条に、百済の肖古王が日本の使者、千熊長彦に会い、七支刀一口、七子鏡一面、及び種々の重宝を献じて、友好を願ったという意味のことが書かれている。