This rare example of a medieval yoroi is characterized by a cuirass that wraps around the body and is closed by a separate panel (waidate) on the right side and by a deep four-sided skirt. In use from around the tenth to the fourteenth century, yoroi were generally worn by warriors on horseback.
This armor was originally laced in white silk and had diagonal bands of multicolored lacings at the edges of the skirt and the now-missing sode (shoulder guards). The colored lacings symbolized the rainbow, which represented both good fortune and fleeting beauty. The breastplate is covered with stenciled leather bearing the image of the powerful Buddhist deity Fudo Myo-o, whose fierce mien and attributes of calmness and inner strength were highly prized by samurai. The helmet, long associated with this armor, dates from the mid-fourteenth century.
This yoroi" is traditionally believed to have been donated to the Shinomura Hachimangu, a shrine near Kyoto, by Ashikaga Takauji (1305–1358), founder of the Ashikaga shogunate.