One of the first recorded instances of the use of soft body armor was by the medieval Japanese, who used armor plate manufactured from silk. It was not until the late 19th century that the first use of soft body armor in the United States was recorded. At that time, the military explored the possibility of using soft body armor manufactured from silk. This form of armor plate project even attracted congressional attention after the assassination of President William McKinley in 1901.
This form of armor plate proved successful after the garments were shown to be effective against low-velocity bullets, those traveling at 400 feet per second or less, but however this armor plate did not offer protection against the new generation of handgun ammunition being introduced at that time. Ammunition that traveled at velocities of more than 600 feet per second. This, along with the prohibitive cost of silk made this new armor plate concept unacceptable. Silk body armor of this type was said to have been worn by Archduke Francis Ferdinand of Austria when he was killed by a shot to the head, thereby precipitating World War I.