Having achieved unity at home, Hideyoshi could afford to devote some thought to restoring Japan’s position in south-east Asia. The vast and apparently stable Chinese empire had grown in relative stature during Japan’s centuries of anarchy, and in order to have a free hand against the potential enemy Hideyoshi decided to invade the nearby peninsula of Korea. The Japanese duly descended on Korea in the spring of 1592, and won a vital bridgehead by storming into Pusan. The Korean forces of easy- going nobles and serf-like peasants thereupon gave way in all directions, and allowed the invaders to occupy the principal town, Seoul, without offering resistance.
After this first run of disasters the ingenious Koreans managed to put up a very creditable performance at sea and around the fortresses in other words in the kinds of war in which technical expertise counted the most
Korean chroniclers leave no doubt that gunpowder appeared in their land at an early date
At the end of 1392 a Chinese merchant .. . stayed in the home of a general in charge of weapons along the River Imjin near Songdo. The general told his servant to treat him kindly (the Koreans always got on well with the Chinese) and the merchant showed him how to mix saltpetre. This was the first time we had powder in Korea (Boots, 1934, 20)
In 1494 an official manual mentions the existence of cannon that were designed to throw stones and arrows, and by 1569 Korean gunnery was advanced enough to produce a large cannon called a ‘flying, striking, earthquake heaven thunder’, which hurled a fuzed explosive or incendiary missile for several hundred yards. The Koreans were backward only in the production of hand weapons, and the matchlock remained unknown to them until the Japanese envoy so unwisely presented them with a specimen in 1589 Many more weapons were captured from the Japanese in the war of 1592, and the Koreans were delighted to discover that you could strike a man down at a distance merely by ‘pointing a dog’s hind leg at him’ (ibid.)
The design of Korean fortifications was distinctive, not to say bizarre. The walls rarely rose more than twenty feet high, and the hundreds of merlons along the crest formed so many miniature citadels, each between six and ten feet long, pierced by three loopholes, and roofed over to the rear. Every stone block of the revetment was dressed on the inner side into a pyramid, which served to fix the masonry into the rampart’s core of earth and loose stones However, the workmanship and materials of the wall were liable to vary a great deal from one section to the other, for the construction was carried on by separate gangs, each with its own way of working. In time of siege the soul of defence was the town prefect, who took up station in the upper storey of the main gate and beat encouraging noises on a great drum. An historian comments that
since the Koreans geometrically and were psychologically always on the defence in warfare, the wall naturally came to be their most respected and efficient weapon. . . . By this mental attitude and the actual physical protection of her walled retreats, Korea was able to maintain for so long her individuality as a nation and to turn her enemies’ assaults into empty victories by holding them for months without their gates until the shortage of supplies and weakened spirit made their ‘victorious’ return home the better part of valour (ibid., 36-7)
These cunning enemies soon made the Japanese regret that they had ever invaded Korea. The Koreans were victorious at sea, thanks largely to an iron-plated ‘tortoise-boat’ of their invention, and on land the guerrillas were so had to maintain heavy garrisons in a series of forts along the communications between Seoul and Pyongyang. The Korean levies under General Pak Jin actually went over to the offensive, and used a ‘flying, striking, earthquake heaven thunder’ to throw a large bomb into the town of Kyongju. The fizzing missile attracted a crowd of Japanese, and repaid their curiosity by blowing bits. The rest of the garrison abandoned the town in active that the Japanese a score of them to terror
Thus the Koreans prolonged their resistance until, early in 1593, the Chinese poured over the Yalu to their help. Pyongyang fell to a Chinese escalade in February, and the Japanese retreated to a series of fortified camps on the south coast (much as the United Nations forces were to do in the face of the North Korean invasion of 1950). The enforced concentration of their troops in the south at least enabled the Japanese to gain their last notable success of the war, when they annihilated the 60,000 or 70,000 Korean defenders of the long-isolated fortress of Chinju. The siege was crude, even by Japanese standards: almost one hundred assaults were repulsed, and the Japanese made their breach only by advancing a ‘sow’ to the corner of a wall and prising the stones loose by crowbars.
The Japanese held their coastal camps against intermittent attack until they concluded peace with the Chinese in 1598. The last of the expeditionary force was withdrawn from Korea not long afterwards.
Siege of Pyongyang
The Siege of Pyongyang was a military conflict fought between the allied Ming-Joseon army and the Japanese First Division under Konishi Yukinaga. The battle ended in victory for the allies but a successful retreat from Pyeongyang by the remaining Japanese in the night of 8 February 1593.
A minor Ming force of 5,000 under Wu Weizhong arrived at the Yalu River on 5 January.
The Ming army of 35,000 under Li Rusong arrived at the Yalu River on 26 January. They were then joined by the advance force and a bodyguard unit sent to protect Seonjo of Joseon, raising their strength to 43,000, another 10,000 Koreans at Sunan under I Il, and finally 4,200 monks under Hyujeong.
Li Rusong sent ahead the envoy Shen Weijing to negotiate with Konishi Yukinaga, however this act was insincere. He had no intention of negotiating with the Japanese. Konishi sent 20 men to greet the Ming envoys, but most of them did not return. It’s not certain what happened to them. One version of events state that they were killed during a banquet with Shen Weijing, another says they were simply ambushed on the way.
During the march to Pyeongyang they encountered a Japanese scout party, three of whom were captured, and five killed. The allied army arrived at Pyeongyang and set up camp north of the city on 5 February 1593.
Konishi offered to hold negotiations but was refused. That night some 800 Japanese sneaked out and attacked the Ming camp, however they were spotted by guards and driven back by fire arrows, suffering 30 casualties.
The battle began on 6 February 1593. Hyujeong’s monks with support from Wu Weizhong attacked the large hill north of Pyeongyang where around 2,000 enemy troops were stationed under Konishi Yukinaga. Konishi was almost surrounded at one point until Sō Yoshitoshi counterattacked and rescued him. The fighting lasted for two days before the last Japanese commander, Matsuura Shigenobu, was forced to pull back to Pyeongyang. The monks suffered 600 casualties and Wu Weizhong was wounded in the chest by a bullet.
In the morning of 8 January, Li Rusong’s army advanced on the city, their tightly packed ranks “looking like the scales on a fish.” Yang Yuan and Zhang Shijue attacked from the north and west, Li Rubai from the southeast, and I Il and Gim Eungso from the southwest. The east was covered by the Daedong River and could not be attacked.
Once the signal cannon fired, they rushed the walls with ladders, shot fire arrows and threw bombs into the city, and started pounding the gates with cannons. The Japanese defense was almost too much. Li Rusong’s own horse was shot out from under him and the assault began to show signs of faltering before Li went forward, cut off the head of a retreating soldier, and offered 5,000 taels to the first man over the wall. The allied troops renewed their assault until Luo Shangzhi was able to clear the wall and Yang Yuan followed by breaking through the northern gate. In the west the surviving monks and troops from the earlier attack joined Zhang Shijue’s push into the city once the gate had been destroyed by cannons.
The Japanese pulled back to their last line of defense, an earth and log fort in the northern corner of Pyeongyang. Li Rusong instructed his troops to set the building on fire using fire arrows, but even so the Japanese could not be dislodged. Instead the crush of allied soldiers and cavalry suffered horrendous casualties to Japanese gunfire. Unable to move forward, many retreated through the western gate. Seeing this, Konishi chose to go on the offensive and sortied out with his men, only to be driven back by cannon fire.
Unwilling to suffer any more casualties, Li Rusong called off the attack as night approached.
Although nominally successful in repelling the enemies, the Japanese were no longer capable of defending the city. All the gates had been breached, no food was left, and they had suffered horrible casualties. With this in mind Konishi led the entire garrison out into the night and snuck across the frozen Daedong River back to Hanseong.
Konishi’s men reached Hanseong on 17 February.
After the Japanese loss at Pyeongyang, Kuroda Yoshitaka called for the removal of Konishi Yukinaga, saying that he was a poor leader and did not get along with his fellow commanders. Konishi, in turn, became the primary advocate for peace on the Japanese side, having suffered one of the heaviest losses during the campaign.
Song Yingchang invited Seonjo of Joseon to return to Pyeongyang on 6 March.
THE IMJIN WAR: JAPAN’S INVASION OF KOREA AND ATTEMPT TO CONQUER CHINA by Samuel Hawley