"Nihonshoki" (Chronicles of Japan) has a description that On hakase (SHOKU Shugen and SATSU Kokaku) existed in 691, and it is known that toraijin (people from overseas, especially from China and Korea, who settled in early Japan and introduced Continental culture to the Japanese) mainly assumed this post.
『日本書紀』持統天皇5年（691年）に音博士（続守言・薩弘格）の存在が記され、主に渡来人がこれを担当したことが知られている。