Siege of Pyongyang ( 1593 ) The Siege of Pyongyang was a battle fought between the Ming - Korea alliance and Japan ese forces during Japanese invasions of Korea . On December 25 , 1592 , the Ming army assembled by the administrator Song Yingchang and led by the general Li Rusong crossed the Yalu river and after a number of small engagements with the Japanese , they met with Joseon forces and together marched towards PyongYang . According to the letters of Song Yingchang ( 經略復國要編 ; " Jīng lüè fù guó yào biān " ) the Ming forces that crossed at the time were roughly 36 , 000 in strength . The two sides combined for a little over 40 , 000 . The Japanese forces were led by Konishi Yukinaga and the entire army of the first division . They were roughly 18 , 000 in strength , and had spent the past few months setting up defenses within the area . However the Japanese forces at the time were stretched thin and their supply lines were overexposed to the numerous insurgents in Korea , a problem made more complicated by the exploit of Yi Sunshin and his navy . Pyongyang was at the very front of their deployment and was in dire supply situation . Arrival and attempts at barter . The allied forces arrived at Pyongyang on 1 / 05 1593 , at the west end of the Pyongyang . The Ming had previously sent their diplomat Shen Weijing to start negotiations with the Japanese in the previous months , and he was present in the army as well . He was sent forth again when the army reached the walls to make attempts at barter , Konishi Yukinaga , realizing their own trouble with logistics , wasn ' t eager to fight the allied forces and agree to meet with Li . Over the next couple of days however , the barter turned into chaos as Li Rusong attempted to capture the Japanese leaders sent to the Ming camp by Konishi during the barter that failed , and after that the Japanese made a similar offer for Li to enter into the city and talk . Li had originally considered a plan where they would agree and storm into the city and take them by surprise , but at the last minute bailed on the plan and decided to go with a direct assault . The battle . After the barter broke down , there were some initial skirmishes at Mount Morobung and the Japanese also attempted a night raid on the Ming position that failed . Early in the morning of January 8 , Li Rusong ordered his forces to attack ; their plan was a three - sided assault , with the primary focus on the west end led by Li Rusong himself . The southern end was led by Zu Chengxun ; his forces were mostly Ming forces disguised as Korean soldiers , this was because the Japanese did not think highly of the fighting abilities of the Koreans , to confuse the Japanese defenders , while the North end was led by Wu Weizhong and his southern troops along with the Korean Monk warriors . Their objective as to take the high grounds on Mt . Morobung just north of the city . According to Chinese accounts , the Ming forces had fired off poisonous rocket arrows early in the morning ( called 毒火飛箭 ; " dú huǒ fēi jiàn " ) to create a stink cloud in the city and nauseate the defenders ( those incendiary arrows were mostly carrying dried excrement ) before the full assault , they fired off huge volleys of incendiary rocket arrows into the city along with artillery barrage before the all out assault commenced . The fighting was fierce on all fronts ; on the north end they directly stormed the Japanese position , Wu Weizhong was hit by a bullet to the chest but managed to continue commanding . On the southern end , the Japanese were confused by the disguised soldiers and thought that the allied forces were not going to actually attack from that side ( as the reputation of the Chosen court army was quiet poor at this time ) . However , they were taken by surprised by the army , which was revealed to be mostly consist of Ming soldiers and attacked the Japanese ' s position . Still , as they were attempting to enter the city streets , the Chinese were hit by ambushes and beaten back . The western end was where the biggest fighting occurred , Li Rusong ' s horse was shot from under him and briefly fell into a pit , Li Rumei ( Li Rusong ' s brother ) took an indirect arquebus shot to the helmet . Many of the allied generals climbed up the ladders with their men and fought on the walls . With his forces in trouble on all fronts , Konishi decided to pull his men back into the citadel they had recently constructed . Encircled in the citadel , Konishi realized that the eastern end of the walls were still open , and at night they retreated out on haste and made a dash for Seoul ; however as they were attempting to ford the Datung River they were hit by further allied ambushes with artilleries and took more casualties . There are contradictions among the different sources on how the Japanese left the city ; Ming sources generally state that it was part of the battle plan to leave a part of the city open so the Japanese defenders would be less inclined to fight to the death . A few Japanese sources cite that the ally forces simply would dare come near their fortifications inside the city , while Korean sources are even more confusing , Yu Seong - ryong ' s Jingborok stated both versions , as first he writes that the Li Rusong ordered the ally forces to not press the attack , and then later wrote that the Korean general Yi Il was punished because Li Rusong was angry that he let the Japanese force slip . , while others said that Li Rusong ordered them not to let the Japanese retreat . This battle probably saw the largest use of artillery in the 16th century , as the Chinese had amassed an arsenal of 200 pieces of various types of artillery , including rocket arrows , breech - loading cannon and several large caliber " Great General " cannons ( Although Song Yingchang ' s letter claimed that the Great Generals did not reach Pyongyang in time as they had intended ) . Both armies used state of art firearms and cannons .