These three collections were made when the new Seii taishogun (literally, "great general who was to subdue the barbarians") started his reign, and it is thought that the editing work was conducted to in line with the new reign began.
以上の3回はいずれも新征夷大将軍の御代始を期に行われており、御代始の新政に合わせて編纂が行われたと考えられている。