Ō-yoroi
armor worn by the samurai class of feudal Japan
The ō-yoroi (大鎧) is a prominent example of early Japanese armor worn by the samurai class of feudal Japan. The term ō-yoroi means "great armor".
History
Ō-yoroi first started to appear in the 10th century during the middle and late Heian period, and came into widespread use in the Genpei War around the 12th century when the call for armor was at its peak. Significant aspects of this armor were designed for cavalry archers. 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.
For the most part the ō-yoroi was a rich man's armor and not used by lower ranking samurai. The armor was mainly worn by the higher ranking samurai on horseback. The lower ranking soldiers had armor that was similar to the ō-yoroi, but had fewer components, was lighter, and lacked the decorative markings of the higher ranking samurai.
Most of the information known about the ō-yoroi is based on the armor of the higher-ranking officials since the armor was either donated to a shrine as an offering or maintained by the descendants of the original wearer. 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.
“Ō-yoroi” enters the record as armor worn by the samurai class of feudal Japan. Crown Archives preserves that source wording while asking what Ō-yoroi, armor and worn can confirm, complicate or overturn.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jun 24, 2026. The linked authority identifier is Q386589. None of the 0 selected statements returned an explicit reference.
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This entry incorporates text from “Ō-yoroi” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.