Following the French naval invasion of Ganghwado Island in 1866 (the 3rd year of King Gojong’s reign), Heungseon Daewongun, King Gojong’s father, ordered the production of bullet-proof armor. As a result of repeated experiments, armorers succeeded in producing suits of armor made of thirteen layers of cotton fabric that could stop bullets. The armor was first used in a standoff against American marines in 1871. It proved effective against bullets, but was useless against fire or moisture. This particular piece of armor is made of thirty layers of cotton fabric, and contains the Chinese characters “孔君玉,” which are presumed to be the owner’s name, on its inner side. As the only extant example of cotton armor in Korea, it is an important material for those studying the history of armor development.