Gonaisho was an official document written in the style of a private letter that was issued by the Seii Taishogun (literally, great general who subdues the barbarians) of the Muromachi bakufu (Japanese feudal government headed by a shogun).
御内書（ごないしょ）は、室町幕府の征夷大将軍が発給した私的な書状の形式を取った公文書。