| Japanese invasions of Korea | |||||||
|---|---|---|---|---|---|---|---|
 The Japanese landing on Busan. |
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| Combatants | |||||||
| Korea under the Joseon Dynasty, China under the Ming Dynasty, Jianzhou Jurchens |
Japan under Toyotomi Hideyoshi | ||||||
| Commanders | |||||||
| Korea King Seonjo China |
Japan Toyotomi Hideyoshi, |
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| Strength | |||||||
| Korea 40,000 Korean Army, China |
Japan 1st.(1592–1593) |
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| Casualties | |||||||
| Korea, China, and Japan
military total 250,000[1] |
civilian + military total 1,000,000[2] | ||||||
| Japanese invasions of Korea (1592-1598) |
|---|
| Busan – Tadaejin – Tongnae – Sangju – Ch'ungju – Okpo – 1st Sacheon – Imjin River – Dangpo – Danghangpo – Hansando – Pyongyang – Chonju – Haejongchang – Busan – Jinju – Pyeongyang – Byokchekwan – Haengju – Jinju – Busan – Hwawangsan – Chilchonryang – Namwon – Myeongnyang – Ulsan – 2nd Sacheon – Noryang Point |
| Korean name | ||||||||
|---|---|---|---|---|---|---|---|---|
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| Japanese name | ||||||||
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| Chinese name | ||||||||
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Two Japanese invasions of Korea and subsequent battles on the Korean peninsula took place during the years 1592–1598. Toyotomi Hideyoshi led the newly unified Japan into these invasions with the professed goal of conquering Ming Dynasty China. The invasions are also known as Hideyoshi's invasions of Korea, the Seven Year War (in reference to its span) and the Imjin War (in reference to the "Imjin" year of the sexagenary cycle in Korean).[3] The Korean name for the war means "the Japanese-started Invasion of the Year of the Dragon"; the Japanese, "Joseon Campaign"; and the Chinese, "the Eastern Pacification".[4]
The first invasion (1592–1593) is literally called the "Japanese (= 倭 |wae|) War (= 亂 |ran|) of Imjin" (1592 being an imjin [= water — dragon] year in the sexagenary cycle) in Korean and Bunroku no eki in Japanese (Bunroku referring to the Japanese era under the Emperor Go-Yōzei, spanning the period from 1592 to 1596). The second invasion (1597–1598) is called the "Second War of Jeong-yu" and "Keichō no eki", respectively. In Chinese, the wars are referred to as the "Renchen (the information about the Imjin year also applies here) War to Defend the Nation" or the "Wanli Korean Campaign", after then reigning Chinese emperor.
Initially, the Japanese forces saw successes on land and consistent failures at sea. However, the Japanese forces came to suffer heavily as their communication and supply lines were thinned. The Korean navy starved the Japanese forces by successfully intercepting the Japanese supply fleets on the western waters of the peninsula, to which most major rivers of the Korean peninsula flow. Ming China under Emperor Wanli brought about a military and diplomatic intervention to the conflict, which China understood as a challenge to its tributary system.[5] The war stalled for five years during which the three countries tried to negotiate a peaceful compromise; however, Japan invaded Korea a second time in 1597. The war concluded with the naval battle at Noryang. All of the Japanese forces in Korea had retreated by the 12th lunar month of 1598 and returned to Japan after the devastating defeat against the Korean navy.
In addition to the human losses, Korea suffered tremendous cultural, economic, and infrastructural damage, including a large reduction in the amount of arable land,[3] destruction and confiscation of significant artworks, artifacts, and historical documents, and abductions of artisans and technicians.[6] The heavy financial burden placed on China by the war adversely affected its military capabilities and contributed to the fall of the Ming Dynasty and the rise of the Qing Dynasty.[7] However, the sinocentric tributary system that Ming had defended was restored by Qing, and the normal trade relations between Korea and Japan continued.[8]
Background
East Asia and the Chinese Tributary System
In 1392, the Korean General Yi Seong-gye led a successful coup against King U of the Goryeo Dynasty, and founded Joseon.[9] In search of a justification for its rule given the lack of a royal bloodline, the new regime received recognition from China and integration into its tributary system within the context of the Mandate of Heaven.[10] Under Ashikaga Yoshimitsu's reign during the late 15th century, Japan, too, gained a seat in the tributary system (lost by 1547, see hai jin).[11][12] Within this tributary system, China assumed the role of a big brother, Korea the middle brother, and Japan the younger brother.[13]
Unlike the situation over a thousand years earlier where Chinese dynasties had an antagonistic relations with the largest of the Korean polities (see List of Chinese invasions of Goguryeo), the Joseon Dynasty had a close trading and diplomatic relations with Ming China, and also a continuous trade relations with Japan.[14] The two dynasties, Ming and Joseon, shared much in common: both emerged during the fourteenth century at the fall of the Mongolian rule, embraced the Confucian ideals in society, and faced similar external threats (the Jurchen raiders and the Japanese Wakō pirates).[15] As for the internal, both China and Korea were troubled with fights among the competing political factions, which would significantly influence the decisions made by the Koreans prior to the war, and those made during the war by the Chinese.[16][17] Dependence on each other for trade and also having common enemies resulted in Korea and Ming China having a friendly relationship.
Toyotomi Hideyoshi and his preparations
By the last decade of the 16th century, Toyotomi Hideyoshi as daimyō had unified all of Japan in a brief period of peace. Since Hideyoshi came to hold power in presence of a legitimate Japanese imperial line, Hideyoshi sought for military power to legitimize his rule and to decrease his dependence on the imperial authority.[18] It is said that Hideyoshi planned for an invasion of China to fulfill which his late leader Oda Nobunaga dreamed of,[19] and to mitigate the possible threat of civil disorder or rebellion posed by the excess number of samurais and soldiers.[20] But it is quite possible that Hideyoshi might have set a more realistic goal of subjugating the smaller neighbouring states (i.e. Ryukyus, Luzon, Taiwan, and Korea), and treat the large or too distant countries as trading partners:[18] all throughout the invasion of Korea, Hideyoshi sought for legal tally trade with China[18] Hideyoshi's need for military supremacy as a justification to his rule that lacked royal background could, on an international level, translate into a Japanocentric order with Japan's neighbouring countries below Japan.[18] Historian Kenneth M. Swope identifies a rumor relevant to the time that Hideyoshi could have been a Chinese who fled to Japan from the law, and therefore sought revenge against China.[21]
The defeat of the Odawara-based Hōjō clan in 1590[22] finally brought about the second unification of Japan,[23] and Hideyoshi began preparing for the next war. Beginning in March 1591, the Kyūshū daimyō and their labor forces constructed a castle at Nagoya (in modern-day Karatsu) as the center for the mobilization of the invasion forces.[24]
Hideyoshi planned for a possible war with Korea long before the completing the unification of Japan, and made preparations on many fronts. As early as in 1578, Hideyoshi then battling under Nobunaga against Mōri Terumoto for control of the Chūgoku region of Japan, informed Terumoto of Nobunaga's plan to conquer China.[25] In 1592 Hideyoshi sent a letter to the Philippines threatening the governor general for tribute and stating that Japan had already received tribute from Korea (which was a misunderstanding, as explained below) and the Ryukyus.[26]
As for the military preparations, the construction of as many as 2,000 ships may have begun as early as 1586.[27] To estimate the strength of the Korean military, Hideyoshi sent an assault of 26 ships to the southern coast of Korea in 1587, and he concluded that the Koreans were incompetent.[28] On the diplomatic front, Hideyoshi began to establish friendly relations with China long before completing the unification of Japan and helped to police the trade routes against the wakō.[29]
Diplomatic dealings between Japan and Korea
In 1587, Hideyoshi sent his first envoy Tachibana Yasuhiro,[30] to Korea then under King Seonjo[31] to re-establish diplomatic relations between Korea and Japan (which was broken since a devastating pirate raid in 1555)[32] which Hideyoshi hoped to use as a foundation to induce the Yi Court to join Japan on war against China.[33] Yasuhiro, with his warrior background and an attitude disdainful of the Korean officials in their customs he considered as effeminate, failed to receive the promise of future ambassadorial missions from Korea.[34] Around May 1589, Hideyoshi's second ambassadors consisting of Sō Yoshitoshi (or Yoshitomo),[35] Gensho and Tsuginobu reached Korea and secured the promise of a Korean embassy to Japan in exchange of the Korean rebels having taken refuge in Japan.[34] In fact, in 1587 Hideyoshi had ordered Sō Yoshinori, the father of Yoshitoshi and the daimyō of Tsushima, to offer Joseon the ultimatum to submit to Japan and participate in the conquest of China, or war with Japan.[36] However, as Tsushima enjoyed a special trading position as the single checkpoint to Korea for all Japanese ships and permission from Korea to trade with as many as 50 of its own vessels,[37] the Sō family delayed the talks for nearly two years.[35] Even when Hideyoshi renewed his order, Sō Yoshitoshi reduced the visit to the Yi Court down to a campaign to better relations between the two countries.[35] Near the end of the ambassadorial mission, Yoshitoshi presented King Seonjo a brace of peafowl and matchlock guns - the first advanced fire-arms to come to Korea.[38] Then Yu Seong-ryong, a high-ranking scholar official, suggested that the military put the arquebus into production and use, but the Yi Court failed to cooperate.[39]
On April 1590, the Korean ambassadors including Hwang Yun-gil, Kim Saung-il and others[40] left for Kyoto, where they waited for two months while Hideyoshi was finishing his campaign against the Odawara and the Hōjō clans.[41] Upon his return, they exchanged ceremonial gifts with and delivered King Seonjo's letter to Hideyoshi.[41] As Hideyoshi assumed that the Koreans had come to pay homage as a tributary to Japan, the ambassadors were not given the formal treatment that was due in handling diplomatic matters; at last, the Korean ambassadors asked that Hideyoshi write a reply to the Korean king, for which they waited 20 days at the port of Sakai.[42] The letter, redrafted as requested by the ambassadors on the ground that it was too discourteous,[42] invited Korea to submit to Japan and join the war against China.[38] Upon the ambassadors' return, the Yi Court held serious discussions concerning Japan's invitation;[43] the ambassadors reported to the Yi Court conflicting estimates of Japan's military strength and intention, all of which were lost in the quarrels of competing political factions and ranks.[32] Some, including King Seonjo, argued that Ming should be informed about the dealings with Japan, as failure to do so could make Ming suspect Korea's allegiance,[44] but the Yi Court finally concluded to wait further until the appropriate course of action became definite.[43]
Hideyoshi initiated his diplomacy with Korea under the impression that Korea was a vassal of Tsushima Island, which the Koreans considered theirs; the Yi Court approached Japan as a country inferior to Korea accordingly within the Chinese tributary system, and it expected Hideyoshi's invasions to be no better than the common Wako pirate raids.[45] The Yi Court handed to Gensho and Tairano, Hideyoshi's third embassy, King Seonjo's letter rebuking Hideyoshi for challenging the Chinese tributary system; Hideyoshi replied with a disrespectful letter, but, since it was not presented in person as expected in custom, the Yi Court ignored it.[46] After the denial of his second request, Hideyoshi launched his armies against Korea in 1592. There were internal oppositions to the invasion within Japan's government; among them, Tokugawa Ieyasu, Konishi Yukinaga and Sō Yoshitoshi tried to arbitrate between Hideyoshi and the Joseon court.[citation needed]
Military Capabilities
The two major security threats to Korea and China at the time were the Jurchens, who raided along the northern borders, and the wakō (Japanese pirates), who pillaged the coastal villages and trade ships.[47][48] In response to the Jurchens, the Koreans constructed a thorough defense line of fortresses along the Tumen River; in response to the Japanese, the Koreans developed a poweful navy and even took control of the island of Tsushima.[49] This defensive environment of relative peace pushed the Koreans to depend on the heavy artillery of fortresses and warships. China bore a much larger responsibility than Korea as the head of its tributary system and had to make adjustments to all sorts of environments.[50] China was the main source of new military technologies in Asia, and excelled in both cannon manufacturing[50] and shipbuilding.[51] Japan, on the other hand, had been in a state of civil war for over a century, so the military had come to favor the muskets adopted from Portugal over such other weapons. This strategic difference in weapons development and implementation contributed to the in-war Japanese dominance on landd, and the Sino-Korean dominance at sea.[50]
As Japan had been at war since the mid-15th century, Hideyoshi had half a million battle-hardened soldiers at his disposal[52] to form the most professional army in Asia.[53] While Japan's chaotic state had left the Koreans with a very low estimate of Japan as a military threat,[54] A new sense of unity among the different political factions in Japan, and the "Sword Hunt" in 1588, the confiscation of all weapons from the peasants, indicated otherwise.[55] Along with the hunt came “The Separation Edict” in 1591, which effectively put to end all Japanese wakō piracy by prohibiting the daimyōs from supporting the pirates within their fiefs.[55] Ironically enough, the Koreans believed that the Hideyoshi’s invasion would be just an extension of the previous pirate raids that had been repelled before.[56] As for the military situation in Joseon, the Korean scholar official Yu Seong-ryong observed, "not one in a hundred [Korean generals] knew the methods of drilling soldiers":[57] rise in ranks depended far more on social connections than military knowledge.[58] Korean soldiers were disorganized, ill-trained and ill-equipped,[59] and they were used mostly in construction projects such as building castle walls.[60]
Problems with the Korean defense policies
There were several defects with the organization of the Korean military.[61] An example was a defense policy that local officers could not individually respond to a foreign invasion outside of their jurisdiction until a higher ranking general, appointed by the king's court, arrived with a newly mobilized army.[61] This arrangement was highly inefficient in that the nearby forces would remain stationary until the mobile border commander arrived to the scene and took control.[61] Secondly, as the appointed general often came from an outside region, he was likely to be unfamiliar with the natural environment, the available technology and manpower of the invaded region.[61] Finally, as a main army was never maintained, new and ill-trained recruits conscripted during war constituted a significant part of the army.[61] The Yi Court managed to carry out some reforms, but even they were problematic. For example, the military training center established in 1589 in the Gyeongsang province recruited mostly the too young or old soldiers (as able men targeted by the policy had higher priorities in farming and other economic activities), augmented by some adventure-seeking aristocrats and slaves buying their freedom.[61]
The dominant form of the Korean fortresses was the "Sanseong", or the mountain fortress,[62] which consisted of a stone wall that continued around a mountain in a serpentine fashion.[53] These walls were poorly designed with little use of towers and cross-fire positions (usually seen in European fortifications) and were mostly low in height.[53] It was a wartime policy for everyone to evacuate to one of these fortresses nearby and for those who failed to do so to be assumed as collaborators with the enemy; however, the policy never gained any effect because the fortresses were out of reach for most refugees.[53]
Troops size
Hideyoshi mobilized his army at the Nagoya castle on Kyūshū, newly built just for the purpose of housing the invasion forces and the reserves.[63] The first invasion consisted of 9 divisions totalling 158,800 men, among which the last two of 21,500 were stationed as reserves in Tsushima and Iki respectively.[64] On the other hand, Joseon maintained only a few military units and no field army, and its defense depended heavily on the mobilization of the citizen soldiers in case of emergency.[60] During the first invasion, Joseon deployed a total of 84,500 regular troops throughout, assisted by 22,000 irregular volunteers.[65] The Chinese aid during the war could not have made up for the difference in numbers since they maintained never more than 80,000 troops in Korea at any point of the war,[66] while the Japanese used a total of 500,000 troops throughout the entire war.[52]
As early as 1582, the Korean scholar official Lee Yul-gok recommended the Yi Court to implement a nationwide expansion of troops up to 100,000, including a conscription of slaves and sons of concubines, after the northern troops performed miserably against a Jurchen attack.[57] However, as Lee was of the Western Faction, the dominant and the competing Eastern Faction (led by Yu Seong-ryong) rejected the proposal.[57] The same result applied to a 1588 proposal from a provincial governor to arm the twenty islands of the southern coast of the peninsula and a proposal in 1590 to fortify the islands around the port city of Busan.[57] Even when the Japanese invasion seemed probable and Yu Seong-ryong switched side on this issue, counter arguments brought purely out of political competition neutralized any gains for those advocating for the expansion of the military.[57]
Weapons
Since its introduction by the Portuguese traders on the island of Tanegashima in 1543,[67] the musket became widely used in Japan.[68] Both Korea and China had already been using firearms similar to the Portuguese arquebus, but the weapon fell into disuse in Korea[28] and the focus for the gunpowder weapons in Korea rested primarily on the artillery and archery.[69] When the Japanese diplomats presented the Yi Court arquebuses as gifts, the Korean scholar official Yu Seong-ryong advocated for the use of the new weapon unsuccessfully.[41]
The Japanese saw a very infrequent use of their katana (curved long sword), which were sharper and longer than the Korean and Chinese counterparts,[70] and relied mostly on the muskets (in combination with their bows[71]) instead.[72]
The Korean infantry was equipped with one or more of the following personal weapons: swords, spears, tridents and bow-and-arrows.[51] The Koreans used one of the most advanced bows in Asia[50] - the composite reflex bow that had different materials laminated together (composite, the application of different characteristics of the materials for specific designs) with an inward curve (reflex) for maximum effectiveness; its maximum range was 500 yards, compared to the 350 yards for the Japanese bows.[73] The Chinese infantry used a variety of weapons, as they had to deal with many different environments throughout their empire, including bows (mainly crossbows),[73] swords (also for its cavalry),[74][75] muskets, smoke bombs and hand grenades.[50]
In the early part of the war, the Japanese gained a significant advantage with its monopoly on guns, which had a greater range of 600 yards[70] and penetrating power than the arrows,[76] and which could be fired in concentrated volleys to make up for its lack of accuracy (at both close and long ranges; the bow and arrow, at long range). However, later into the war, the Koreans and Chinese adopted and increased the use of the Japanese muskets.[41][77] It has also been claimed that the Chinese developed bullet-proof suits for use during the second invasion.[78]
Both Korea and China deployed their cavalry divisions in action, however with much negative results. The mountainous environment in Korea, which lacked both the flat plains suitable for cavalry charges and the grass essential in feeding the horses, and the Japanese use of muskets at long range and the katana swords in melee combat put cavalry units at a disadvantage.[75]
Korean cavalrymen were equipped with flails and spears (longer than the Japanese swords) for melee combat and bows and arrows for ranged engagement.[79] Most of the cavalry action for the Koreans took place in the Battle of Chungju at the beginning of the war where the they were outnumbered and wiped out by the Japanese infantry.[79] The Japanese divisions included cavalry as well, sometimes equipped with guns designed smaller specifically for use on horseback.[70] The Japanese use of cavalry was reduced by their previous civil war experiences with the use of guns in concentrated volleys.[80]
Armor
While even the common foot soldier in Japan wore chainmail and bamboo armor, Korean soldiers had almost no armor at all.
Korean foot soldiers wore a heavy leather black vest over their common white clothes and a strictly ceremonial felt hat that offered some protection. Other than this, only the elite soldiers stationed at Seoul (the capital) had armor. Korean captains and generals wore chainmail and scale armor, with shoulder, leg and chest plates. Often, a padded piece of leather was worn around the waist for protection as well.
The Korean military believed that the soldiers did not need armor because emphasis was placed on ranged weapons and agility/maneuverability, instead of hand-to-hand combat.
Naval power
The allies' lead in the artillery technology also gave their navies a tremendous advantage. Especially with the complete lack of cannons on the Japanese ships in the first phase of the war,[51] the Korean and Chinese fleets could bombard the Japanese ships while remaining outside of the retaliatory range of the Japanese muskets, arrows, and catapults.[51] Even when the Japanese attempted to add more cannons to their fleet,[81] their lightweight ship design prevented them from placing as many cannons on board as the allies.[82]
There were fundamental design flaws with the Japanese ships: first of all, most of the Japanese ships were merchant ships modified for the transportation of troops;[51] (it should be also noted that fishing vessels made up for much of the Korean navy)[83] second, the Japanese ships each contained a single square sail (effective only in favorable winds) while Korean ships could be powered by both sails and oars. Also, Japanese ships had V-shaped bottoms (also the Chinese ships as well) that were ideal for speed but were less maneuverable than the flat-bottomed panokseons; and fourth, the Japanese ships relied on nails to hold its wood together while the Korean panokseons used wooden pegs, and this difference added onto the Korean advantage because, in water, nails corroded and loosened while wooden pegs expanded and strengthened the joints.
It should be noted that Hideyoshi tried but failed to hire two Portuguese galleons to join the invasion.[84]
First invasion (1592–1593)
| First wave of the Japanese invasion[85] | |||
|---|---|---|---|
| 1st div. | Konishi Yukinaga | 7,000 | |
| Sō Yoshitoshi | 5,000 | ||
| Matsuura Shigenobu | 3,000 | ||
| Arima Harunobu | 2,000 | ||
| Ōmura Yoshiaki (ja) | 2,000 | ||
| Gotō Sumiharu | 700 | 18,700 | |
| 2nd div. | Katō Kiyomasa | 10,000 | |
| Nabeshima Naoshige | 12,000 | ||
| Sagara Yorifusa (ja) | 800 | 22,800 | |
| 3rd div. | Kuroda Nagamasa | 5,000 | |
| Ōtomo Yoshimasa | 6,000 | 11,000 | |
| 4th div. | Shimazu Yoshihiro | 10,000 | |
| Mōri Yoshimasa (ja) | 2,000 | ||
| Takahashi Mototane (ja), Akizuki Tanenaga, Itō Suketaka (ja), Shimazu Tadatoyo[86] | 2,000 | 14,000 | |
| 5th div. | Fukushima Masanori | 4,800 | |
| Toda Katsutaka | 3,900 | ||
| Chōsokabe Motochika | 3,000 | ||
| Ikoma Chikamasa | 5,500 | ||
| Ikushima (Kurushima Michifusa)? | 700 | ||
| Hachisuka Iemasa (ja) | 7,200 | 25,000 (sic) | |
| 6th div. | Kobayakawa Takakage | 10,000 | |
| Kobayakawa Hidekane, Tachibana Muneshige, Tachibana Naotsugu (ja), Tsukushi Hirokado, Ankokuji Ekei | 5,700 | 15,700 | |
| 7th div. | Mōri Terumoto | 30,000 | 30,000 |
| Subtotal | 137,200 | ||
| Reservers (8th div.) | Ukita Hideie (Tsushima Island) | 10,000 | |
| (9th div.) | Toyotomi Hidekatsu (ja) and Hosokawa Tadaoki (ja) (Iki Island) | 11,500 | 22,500 |
| Subtotal | 158,700 | ||
| Naval force | Kuki Yoshitaka, Wakisaka Yasuharu, Katō Yoshiaki, Otani Yoshitsugu | 9,000 | |
| Subtotal | 167,700 | ||
| Stationed force at Nagoya | Ieyasu, Uesugi, Gamō, and others | 75,000 | |
| Total | 234,700 | ||
The initial attacks
Busan and Tadaejin
On May 23, 1592, the First Division of 7,000 men led by Konishi Yukinaga[87] left Tsushima in the morning, and arrived at the port city of Busan in the evening.[88] The Korean naval intelligence had already detected the Japanese fleet, but Won Gyun, the Right Naval Commander of Gyeongsang, mistook the fleet to consist of trading vessels on a mission.[89] A later report of an arrival of additional 100 Japanese vessels raised his suspicions, but the general did nothing about it.[89] Sō Yoshitoshi landed alone on the Busan shore to ask the Koreans for a safe passage to China for the last time; the Koreans refused, and Sō Yoshitoshi hit the city while Konishi Yukinaga attacked nearby fort of Tadaejin the next morning.[88] Japanese accounts claim that the battles provided the Koreans a complete annihilation (one claims 8,500 deaths, and another, 30,000 heads), while a Korean account claims that the Japanese themselves took significant losses before sacking the city.[90]
Dongnae
On the morning of May 25, 1592, the First Division arrived at the mountain fortress (sanseong) of Dongnae.[90] The fight lasted twelve hours, killed 3,000, and resulted in a Japanese victory.[91] A popular legend describes the governor in charge of the fortress, Song Sang-hyeon. When Konishi Yukinaga again demanded, before the battle, that the Koreans allow the Japanese to travel through the peninsula, the governor replied, "It is easy for me to die, but difficult to let you pass."[91] Even when the Japanese troops during the battle neared his commanding post, Song remained seated with cool dignity.[91] And when a Japanese cut off Song's right arm holding his staff of command, Song picked up the staff with his left arm, which was then cut off; again Song picked it up, this time with his mouth, but was killed by a third blow.[91] The Japanese, impressed by Song's defiance, treated his body with proper burial.[91]
The occupation of the Gyeongsang Province
Katō Kiyomasa's Second Division landed in Busan on May 27, and Kuroda Nagamasa's Third Division, west of Nakdong, on May 28.[92] The Second Division took the abandoned city of Tongdo on May 28, and captured Kyongju on May 30.[92] The Third Division, upon landing, captured the nearby Kimhae castle by keeping the defenders under pressure with the guns while building ramps onto the walls with bundles of crops.[93] By June 3, the Third Division captured Unsan, Changnyong, Hyonpung, and Songju.[93] Meanwhile, Konishi Yukinaga's First Division passed the Yangsan mountain fortress (captured on the night of the Battle of Dongnae, when its defenders fled at the Japanese scout party's fire of their arquebuses), and captured the Miryang castle on the afternoon of May 26.[94] The First Division secured the Chongdo fortress in the next few days, and destroyed the city of Daegu.[94] By June 3, the First Division crossed the Nakdong River, and stopped at the Sonsan mountain.[94]
Joseon response
Upon receiving the news of the Japanese attacks, the Joseon government appointed General Yi Il as the mobile border commander, as was the established policy.[95] General Yi headed to Myongyong near the beginning of the strategically important Choryong pass to gather troops, but he had to travel further south to meet the troops assembled at the city of Daegu.[94] There, General Yi moved all troops back to Sangju, except for the survivors of the Battle of Dongnae who were to be stationed as a rearguard at the Choryong pass.[94]
Battle of Sangju
On April 25,[96] General Yi deployed a force of less than 1,000 men on two small hills to face the nearing First Division.[97] Assuming that a smoke rising was from the burning of buildings by a very nearby Japanese force, General Yi sent an officer to scout on a horse; however, when he neared a bridge, the officer was ambushed by a Japanese musket fire from below the bridge, and beheaded.[97] The Korean troops watching him fall were greatly demoralized.[97] Soon the Japanese began the battle with their arquebus; the Koreans replied with their arrows, which fell short of their targets.[97] The Japanese forces, having been divided into three, attacked the Korean lines from both the front and the two flanks; the battle was over with General Yi Il’s retreat and 300 casualties.[97]
Battle of Chungju
General Yi Il then planned to use the Choryong pass, the only path through the western end of the Sobaek mountain range, to check the Japanese advance.[97] However, another commander, Sin Rip, appointed by the Joseon government had arrived to the area with a cavalry division, and moved the total sum of 8,000 combined troops to the Chungju fortress, located above the Choryong pass.[98] General Sin Rip then decided to fight a battle on an open field ideal for the deployment of his cavalry unit, and placed his units on the open fields of Tangeumdae.[98] Furthermore, the general feared that, since the cavalry consisted mostly of new recruits, his troops would flee in battle easily,[99] and felt the need to trap his forces in the triangular area formed by the convergence of the Talchon and Han rivers in shape of a “Y”.[98] However, the field was dotted with flooded rice paddied, and was not suitable for cavalry action.[98]
On June 5, 1592 the First Division of 18,000 men[99] led by Konishi Yukinaga left Sangju, and reached an abandoned fortress at Mungyong by night.[100] The next day, the First Division arrived at Tangumdae in the early afternoon, where they faced the Korean cavalry unit. Konishi divided his forces into three, and attacked with arquebuses from both flanks and the front.[100] The Korean arrows missed the Japanese troops, outside their range, and General Sin led two charges that failed against the Japanese lines. General Sin then killed himself in the river, and the Koreans that tried to escape by the river either drowned in the river, or were decapitated by the pursuing Japanese.[100]
Capture of Seoul
The Second Division led by Katō Kiyomasa arrived at Chungju, with the Third Division not so far behind.[101] There Katō expressed his anger against Konishi for not waiting at Busan as planned, and attempting to take all of the glory for himself; then Nabeshima Naoshige proposed a compromise of dividing the Japanese troops into two separate routes to Hanseong (the capital and the present-day Seoul), and allowing Katō Kiyomasa to choose the route that the Second Division would take to reach Seoul.[101] The two divisions began the race to capture Hanseong on June 8, and Katō took the shorter route across the Han River while Konishi went further upstream without any waters posing as large barriers.[101] Konishi arrived at Hanseong first on June 10 while the Second Division was halted the river with no boats to cross.[101] The First Division found the castle undefended but its gates tightly locked, as King Seonjo had fled the day before.[102] The Japanese broke into a small floodgate, located in the castle wall, and opened the door capital city gate from the behind.[102] Katō’s Second Division arrived at the capital the next day (by taking the same route as the First Division), and Third and Fourth Divisions the day after.[102] Meanwhile, Fifth, Sixth, Seventh, and Eighth Divisions had landed on Busan, with the Ningth Division reserved on the island of Iki.[102]
Parts of Hanseong had already been looted, burnt (i.e. bureaus holding the slave records and the weapons), and abandoned by its inhabitants.[102] General Kim Myong-won in charge of the defenses along the Han River had retreated.[103] The King’s subjects stole the animals in the royal stables and fled before he, leaving the King to rely farm animals.[103]In every village, the King’s party was met by its inhabitants, lined up by the road, grieving that their King was abandoning them, and neglecting their duty of paying homage.[103] Parts of the southern shore of the Imjin River was burnt to deprive the Japanese troops of materials to arrange their crossing with, and General Kim Myong-won deployed 12,000 troops at five points along the river.[103]
Japanese campaigns in the north
The crossing of the Imjin River
While the First Division rested in Hanseong, the Second Division began north, only to be hampered by the Imjin River for two weeks.[103] The Japanese sent a familiar message to the Koreans on the other shore requesting them to open way to China, but the Koreans rejected.[103] Then the Japanese retreated its main forces to the safety of the Paju fortress; the Koreans saw this as a retreat, and launched an attack at dawn against the remaining Japanese troops on the southern shore of the Imjin River.[103] The main Japanese body retaliated against the isolated Korean troops, and acquired their boats; at this, the Korean General Kim Myong-won retreated with his forces to the Kaesong fortress.[104]
The distribution of the Japanese forces in 1592
With the Kaesong castle having been sacked shortly after (General Kim Myong-won retreated to Pyeongyang),[104] the Japanese troops divided their objectives as thus: the First Division would pursue the Korean king in the Pyongan Province in the north (where Pyongyang is located); the Second Division would attack the Hamgyong Province in the northeastern end of Korea; the Sixth Division would attack the Jeolla Province at the southwestern tip of the peninsula; the Fourth Division would secure the Gangwon Province on the midwestern part of the peninsula; and the Third, Fifth, Seventh, and Eighth Divisions would stabilize the following provinces respectively: the Hwanghae Province (below the Pyongan Province), Chungchon Province (below the Kyonggi Province); Gyeongsang Province (southeastern part where the Japanese first landed); and the Gyeonggi Province (where the capital city is located).[105]
Capture of Pyeongyang
The First Division under Konishi Yukinaga progressed up north, and sacked Pyongsan, Sohung, Pungsan, Hwangju, and Chunghwa on the way.[106] At Chunghwa, the Third Division under Kuroda Nagamasa joined the First, and continued to the city of Pyeongyang located behind the Taedong River.[106] 10,000 troops guarded the city against the 30,000 Japanese troops[107] under the various commands including the General Yi Il and Kim Myong-won, and their defense preparations made sure that no boats were available for Japanese use.[106]
On the night of July 22, 1592, the Koreans silently crossed the river and launched a successful surprise attack against the Japanese encampment.[106] However, this stirred up the rest of the Japanese army, which took the rear of the Korean positions and destroyed the reinforcements crossing the river.[108] Then the rest of the Korean troops retreated back to Pyeongyang, and the Japanese troops gave up their pursuit against the Koreans to observe the way the Koreans crossed the river.[108]
The next day, the Japanese began sending troops to the other shore over the shallow points in the river, in a systematical manner, and at this the Koreans abandoned the city over the night.[109] On July 24, the First and Third Divisions entered the deserted city of Pyeongyang.[109]
Campaigns in the Gangwon Province
The Fourth Division under the command of Mōri Yoshinari set out eastward from the capital city of Hanseong in July, and captured the fortresses down the eastern coast from Anbyon to Samchok.[109] The division then turned inward to capture Chongson, Yongwol, and Pyongchang, and settled down at the provincial capital of Wonju.[109] There Mōri Yoshinari established a civil administration, systematized social ranks according to the Japanese model, and conducted land surveys.[109] Shimazu Yoshihiro, one of the generals in the Fourth Division, arrived to Gangwon lately due to the Umekita Rebellion, and finished the campagin by securing Chunchon.[110]
Campaigns in the Hamgyong Province and Manchuria
Katō Kiyomasa led the Second Division of more than 20,000 men went across the peninsula to Anbyon within ten days' march, and swept north along the eastern coast.[110] Among the castles captured was Hamhung, the provincial capital of the Hamgyong Province, and here a part of the Second Division was allocated for defense and civil administration.[111]
The rest of the division at 10,000 men[107] continued north, and fought a battle on August 23 against the southern and northern Hamgyong armies under the commands of Yi Yong and Han Kuk-ham at Songjin (present-day Kimchaek).[111] A Korean cavalry division took advantage of the open field at Songjin, and pushed the Japanese forces into a grain storehouse.[111] There the Japanese barricaded themselves with bales of rice, and successfully repelled off a formation charge from the Korean forces with their arquebuses.[111] While the Koreans planned to renew the battle in the morning, the Katō Kiyomasa ambushed them at night; the Second Division completely surrounded the Koreans forces with the exception of an opening leading to a swamp.[111] Here, those that fled were trapped and slaughtered.[111]
Koreans who fled gave alarms to the other garrisons, allowing the Japanese troops to easily capture Kilchu, Myongchon, and Kyongson.[111] The Second Division then turned inland through Puryong toward Hoeryong where two Korean princes had taken refuge.[111] And on August 30, 1592, the Second Division entered into Hoeryong where Katō Kiyomasa received the Korean princes and the provincial governor Yu Yong-rip, having already been captured by the local inhabitants.[111] Shortly afterward, a Korean warrior band handed over the head of an anonymous Korean general, and the General Han Kuk-ham tied up in ropes.[111]
Katō Kiyomasa then decided to attack a nearby Jurchen castle across the Tumen River in Manchuria to test his troops against the “barbarians”, as the Koreans called the Jurchens (“oranke” in Korean and “orangai” in Japanese – the Japanese derived both the word and the concept of the Jurchens as barbarians from the Koreans).[112] The Koreans with 3,000 men at Hamgyong joined in (with Kato’s army of 8,000), as the Jurchens periodically raided them across the border.[112] Soon the combined force sacked the castle, and camped near the border; after the Koreans left home, the Japanese troops received a retaliatory assault from the Jurchens.[112] Despite having the advantage, Katō Kiyomasa retreated with his forces to avoid heavy losses.[112]
The Second Division continued east, capturing the fortresses of Chongsong, Onsong, Kyongwon, and Kyonghung, and finally arrived at Sosupo on the estuary of the Tumen River.[112] There the Japanese rested on the beach, and watched a nearby volcanic island rising on the horizon that they mistook as Mount Fuji.[112] After the tour, the Japanese continued their previous efforts to bureaucratize and administrate the province, and allowed several garrisons to be handled by the Koreans themselves.[113]
The naval battles of Admiral Yi
Having secured Pyeongyang, the Japanese planned to cross the Yalu River into China, and use the waters west of the Korean peninsula to supply the invasion.[114] However, Yi Sun-sin, who held the post of the Left Naval Commander (equivalent of "Admiral” in English) of the Jeolla Province (which covers the western waters of Korea), successfully destroyed the Japanese ships transporting troops and supplies.[114] Thus the Japanese, now lacking enough arms and troops to carry on an invasion into China, changed their objective of the war to the occupation of Korea.[114]
When the Japanese troops hit the port of Busan, Bak (also spelled Park) Hong, the Left Naval Commander of the Gyeongsang Province, destroyed his entire fleet, his base, and all armaments and provisions, and fled.[89] Won Gyun, the Right Naval Commander, also destroyed and abandoned his own base, and fled to Konyang with only four ships.[89] Therefore, there was no Korean navy active around the Gyeongsang Province, and the surviving two, out of the total four, navies were active only on the other side of the peninsula.[89] Admiral Won later sent a message to Admiral Yi that he had fled to Konyang after being overwhelmed by the Japanese in a fight.[115] A messenger was sent by Admiral Yi to the nearby island of Namhae to give Yi’s order for war preparations, only to find it pillaged and abandoned by its own inhabitants.[115] As soldiers began to flee secretly, Admiral Yi ordered “to arrest the escapees and had two of the fugitives brought back, beheaded them and had their heads exposed”.[115]
Battle of Okpo
Admiral Yi relied on a network of local fishermen and scouting boats to receive intelligence of the enemy movements.[116] On the dawn of June 13, 1592, Admiral Yi and Admiral Yi Ok-gi set sail with 24 Panokseons, 15 small warships, and 46 boats (i.e. fishing boats), a