Ō-yoroi

The ō-yoroi (大鎧) is a prominent example of early Japanese armor worn by the samurai class of feudal Japan.

[1] The box shaped ō-yoroi was heavy and did not allow as much movement or flexibility as its counterpart the dō-maru, so the armor fell out of favor in the fifteenth century when samurai shifted to mostly infantry tactics.

[3][5] Many of the original components of the ō-yoroi still in existence have been replaced over time due to the items being lost or damaged.

The few remaining examples of ō-yoroi are on display in museums (in several different countries) or in Shinto shrines where they have been maintained and protected for centuries.

[6][3] The basic components of the ō-yoroi and other samurai armor are known collectively as the "hei-no-rokugu" or simply "rokugu," which means six articles of arms.

[4] The six major components are the dō (cuirass), kabuto (helmet), menpo (mask), kote (armoured sleeves), sune-ate (greaves), and the hai-date (cuisses).

One specific advance over earlier armors is that the kozane of ō-yoroi are first laced together and then covered with lacquer, which enhances resistance to corrosion.

The rest of the dō was constructed with individual lacquered scales (kozane) laced together and covered with leather on top.

[9] Facial armor called mengu[10] was worn to protect the samurai's face as part of the full yoroi.

Due to the weight of iron, armour makers limited its use to cover the vitals, and substituted leather for the rest.

The boxy shape hindered the samurai from using the sword with the free, fluid motion vital in hand-to-hand combat, hence the use of yari.