Although the origin of Kousatsu has not been clearly identified, Daijokanpu (official documents issued by Daijokan, Grand Council of State) issued in 782 describes the order of notifying the contents of kanpu to general public by setting up Kosatsu at government offices or on major streets.
その起源は確かでないものの、延暦元年（782年）の太政官符に官符の内容を官庁や往来に掲示して、民衆に告知するように命じた指示が出されている。