In the Heian period, white clothing used by people in the Imperial court as part of layered clothing, including silk costumes worn by emperors at the time of Shinto rituals, was generally called 'Shiro Shozoku.'
平安時代には天皇が神事を行う際に用いた帛の装束を初め、宮廷の男女が装束において重ね着をした際の白衣を広く「白装束」と呼んでいる。