The Nanbandō (Japanese: 南蛮胴) refers to a Japanese armor that is modeled after Western armors, as they arrived in Japan with the Portuguese and Spaniards in the 16th century.
The most important element was the cuirass, a pointed iron plate that covered the entire torso in one piece, tapering to a point at the waist.
This form offered better protection against firearms than the completely unsuitable traditional armors of the Samurai. Arm protection, face mask, armored apron (Kusazuri), shin guards, and decoration, however, were still in the Japanese style, modeled after the Tōseigusoku.
Some armors were so sturdily made that they were considered bulletproof. Due to the cuirass, this armor had a high weight, and even though these armors could be completely manufactured by Japanese craftsmen, they were expensive to acquire. Therefore, they were primarily worn by warlords like Oda Nobunaga and Tokugawa Ieyasu.
The Nanbandō, along with modern artillery and the gun (Teppō), was the third important innovation on the battlefields of the Sengoku period that came to Japan with the Nanban trade.