It’s said history doesn’t repeat itself, but it often rhymes.
In the late 14th century, Korea’s ruling Joseon dynasty began an all-out espionage campaign to acquire classified missile technology from neighboring China. At the time, stateless *wokou “*dwarf pirates”—so called because of their comparatively shorter stature—were ravaging the Korean coast from bases in Japan. The Joseon dynasty sought effective artillery to serve as a deterrent.
This piece was originally published in 2017.
China was then the global leader in gunpowder and rocket technology. However, early rockets were highly inaccurate and mostly useful for panicking the horses of enemy cavalry units. Furthermore, while the Joseon were nominally allied to Imperial China, the Chinese were not willing to transfer the gunpowder technology to their eastern neighbor.
So in 1377 the Korean government formed an Office of Gunpowder Weapons which began clandestinely smuggling classified documents and gunpowder samples out of the Middle Kingdom. This weapons program made a breakthrough when a Chinese merchant was bribed into passing over the formula for gunpowder. At the same time, Korean inventor Choe Mu-seon independently figured out how to synthesize gunpowder from the soil.
Korean inventors went on to develop an extraordinary assortment of gunpowder weapons including tube-launched exploding rockets, chongtong cannons, and arquebuses—or primitive matchlock muskets. Starting in 1380, Korean warships used the gunpowder weapons to crush the dwarf pirate threat in sea battles.
The wokou were finally eradicated when in 1419 a huge gun and rocket-armed Korean expeditionary fleet wiped out the pirates’ boats in a raid on Tsushima Island, Japan. Just prior to that, Yi Do and Choi Hae-san developed a deadly new missile system developed out of straightforward logic. If a lone hwajon fire rocket was unlikely to hit a target—why not fire dozens or hundreds at once?