Choe Mu-seon

Choe Museon
Hangul	최무선
Hanja	崔茂宣
Revised Romanization	Choe Mu-seon
McCune–Reischauer	Ch'oe Musŏn

Choe Mu-Seon (1325–1395) was a medieval Korean scientist, inventor, and military commander during the late Goryeo Dynasty and early Joseon Dynasty. He is best known for enabling Korea to domestically produce gunpowder by obtaining a recipe for the Chinese commodity from a Chinese merchant, as well as inventing various gunpowder-based weapons in an attempt to repel the wokou pirates that plundered coastal regions of the Korean Peninsula.

Choe was born into a wealthy family in Yeongcheon, Gyeongsang province; his father was an official in the administration. He qualified to be a military officer through civil service examination. The government's control of Goryeo was crumbling, and at the same time the pirates crossing the Korean Strait plundered much of the coastal regions. In the southern part of the nation, pirates even marched deep inland, causing havoc. The Goryeo government was not able to ensure security, despite the efforts of generals Yi Song Gye and Choi Yong.

In his childhood, while he was at the royal palace with his father, who was working for the king, Choe saw fireworks made by Mongols and Chinese, who at the time had indirect control of Goryeo (their influence was repealed by King Gongmin). Later in life, Choe embarked on a quest to bring the recipe of gunpowder to Korea. He visited China, which was then ruled by the Mongolian Yuan Dynasty. In general, technology of that region, such as cotton growing and gunpowder manufacture, was kept secret. Choe sought to smuggle some examples of secret items, and eventually was able to obtain knowledge of the three key ingredients of gunpowder: sulfur, slack or fine coal, and potassium nitrate. However, the process to obtain niter, the mineral form of potassium nitrate, was difficult, and he did not know how to prepare gunpowder from the raw materials.

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