Korean cannon

Cannons were first introduced to Korea as early as the Mongol Invasions in 1231-1259, but were not widely used until Choe Mu-seon made Korea's first native gunpowder and gunpowder weapons in the 1370s. These were used by Goryeo's army and to great effect by the navy against the Waegu pirates in 1380 and again in 1383. By 1410, Korea had 140 ships equipped with gunpowder artillery.

Other firearms were used, but were actually hand cannons, and later, arquebuses and muskets.

Choe Mu-seon made various weapons in his Hwatong Dogam, a gunpowder development laboratory established for him by U of Goryeo. Among the gunpowder weapons used (but not necessarily invented by Choe) at this time were: a series of cannons called the daejanggun, ijanggun, and samjanggun, a shell-firing mortar called the jillyeopo, series of yuhwa, juhwa, and chokcheonhwa rockets, which were the forerunner of the shin'gijeon, and a signal gun called the shinpo. Written records for these cannons come from the Goryeosa, Hwayaksuryunbeop (화약수련법/火藥修鍊法), Hwapobeop (화포법/火砲法), and the Annals of the Joseon Dynasty.

During Taejong's rule, improvements were made. Among the people responsible for the developments was Choe Hae-san, the son of the aforementioned Choe Mu-seon. The cheon "heaven" or "sky", ji "earth", hyeon "black", and hwang "yellow" or "gold" names are not significant, being the first four characters of the Thousand Character Classic, thus making them equivalent to Cannons A, B, C, and D. The following is a list some of the main cannons (called hwapo "fire gourd") of this time period:

Written records for cannons of this era come from the Annals of the Joseon Dynasty.

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