As far back as the seventh century Japanese warriors wore a form of lamellar armor, this armor eventually evolved into the armor worn by the samurai. The first types of Japanese armors identified as samurai armor were known as yoroi. These early samurai armors were made from small individual scales known as kozane. The kozane were made from either iron or leather and were bound together into small strips, the strips were coated with lacquer to protect the kozane from water. A series of strips of kozane were then laced together with silk or leather lace and formed into a complete chest armor (dou or dō).
Is there an answer to this question (If it cannot be answered, say "unanswerable"): What was the first samurai armor called?
yoroi