This custom spread especially after the emperor temporarily moved to the Muromachi Palace due to the Onin War, but it was not permitted to enter the court of the emperor's palace in shitasugata, except for the Sekke (the family of Regent).
特に応仁の乱で室町殿に一時天皇が移ると、この習慣は広まったが、摂家などを除き、下姿の時は天皇の御殿に昇殿することは許されなかった。