Japanese suit of armour, 17th Century. Cincinnati Art Museum Japanese armour originated in the 4th century, with early cuirasses and helmets found in graves. During the Heian period (794–1185), distinctive samurai armour styles such as the ō-yoroi and dō-maru emerged, featuring lacquered leather and iron scales laced together with silk.
In the Sengoku period (1467–1615), warfare changed with the rise of ashigaru foot soldiers and the introduction of Portuguese matchlock guns. These developments led to the creation of tosei-gusoku ("modern armour"), which was lighter, simpler, and better suited to firearms.
During the peaceful Edo period (1603–1868), samurai continued wearing armour mainly as a symbol of status. Today, important collections of historic Japanese armour are preserved at Ōyamazumi Shrine and Kasuga Grand Shrine. A tradition also survives on Children's Day (May 5), when families display miniature samurai armour and helmets to celebrate strength and protection.
