Korean History › Late Joseon
Imjin War (Japanese invasions of Korea)
1592–1598· War· Wars & invasions
Well documentedSolid records, physical evidence or scientific consensus.
Japan's two invasions of Korea under Toyotomi Hideyoshi, fought off by Joseon with Ming Chinese help over seven years.
See it on the Korean History map →What happened
Koreans call it Imjin waeran (임진왜란); Japan, the Bunroku-Keichō campaigns; China, the Wanli Korean campaign. In May 1592 about 160,000 Japanese troops, veterans with muskets, landed at Busan. They took Seoul within three weeks and Pyongyang by July; King Seonjo fled to the Chinese border. Yi Sun-sin's navy, righteous armies and Ming armies stalled them. Peace talks failed; Japan invaded again in 1597. After Hideyoshi died in 1598, Japan withdrew. Korean deaths ran from hundreds of thousands to over a million; estimates vary.
Why it matters
It wrecked Joseon's land, population and records, drained Ming China, and produced Korea's foremost national hero; Korean potters taken captive transformed Japanese ceramics.
How we know
Yi Sun-sin's war diary, minister Yu Seong-ryong's memoir Jingbirok, the Sillok, Japanese commanders' letters and diaries, and Ming records; each side's accounts differ.
Still debated
Hideyoshi's real aim (conquering China as he announced, or something more limited) and the true death toll are still debated.
Inside this (3)
Connections (11)
▸Yi I (Yulgok) warned of military weakness before Imjin War (Japanese invasions of Korea)Debated
The connection
Yi I warned repeatedly that Joseon's army and finances were hollow. Tradition says that in 1583 he urged training 100,000 soldiers against a coming crisis and was ignored, nine years before Japan invaded. If true, it made him a prophet of the disaster.
When and how
About 1582–1583 in Hanyang (Seoul), while Yi I served as Minister of War under King Seonjo.
How sure are we?
His reform memorials are genuine, but the 100,000-man plan appears only in his disciples' writings and the Westerner-revised annals, not the original Seonjo sillok.
Debates and open questions
Many historians think followers added the 100,000-army story to glorify him; others accept it. Either way, he did not predict Japan specifically.
▸Factional politics (bungdang) hampered preparations for Imjin War (Japanese invasions of Korea)Debated
The connection
In 1590 Joseon sent envoys to Japan. The Westerner chief envoy Hwang Yun-gil reported that Hideyoshi would invade; his Easterner deputy Kim Seong-il said he would not. The court, then led by Easterners, leaned toward Kim, partly to avoid panic, and preparations stayed limited.
When and how
1590–1591; the envoys returned to Hanyang (Seoul) in early 1591. King Seonjo, Hwang Yun-gil, Kim Seong-il and chief minister Yu Seong-ryong.
How sure are we?
The Sillok and Yu Seong-ryong's Jingbirok record the conflicting reports, and also real preparations, such as Yi Sun-sin's appointment.
Debates and open questions
How much factional bias, versus honest uncertainty, shaped the reports is debated, as is whether more preparation could have stopped Japan's veteran army.
▸Gyeongbokgung Palace was burned during Imjin War (Japanese invasions of Korea)Well documented
The connection
When King Seonjo fled Seoul in 1592, ahead of the Japanese advance, Gyeongbokgung and the other palaces burned. The site lay in ruins for about 270 years; kings lived at the rebuilt Changdeokgung until Heungseon Daewongun rebuilt Gyeongbokgung in 1865–1867.
When and how
June 1592 in Hanyang (Seoul), between the king's flight and the Japanese entry into the city.
How we know
Korean and Japanese sources agree the palace burned in 1592, and it stood in ruins until the 1860s.
Debates and open questions
Who set the fire is disputed: a later Korean annal blames Seoul crowds angry at the fleeing king; popular memory blames Japanese troops; some Japanese accounts say it was already burned.
▸Toyotomi Hideyoshi launched Imjin War (Japanese invasions of Korea)Well documented
The connection
Having unified Japan, Hideyoshi demanded that Joseon join him or let his armies pass to conquer Ming China. When Joseon refused, he sent about 160,000 troops in 1592 and, after peace talks collapsed, about 140,000 more in 1597, directing both campaigns from Nagoya Castle in Kyushu.
When and how
Planned 1587–1591; armies sailed from Nagoya (in today's Saga Prefecture, Kyushu) to Busan in May 1592 and again in 1597.
How we know
Hideyoshi's own letters announcing plans to conquer China and even India, his army rosters, and Korean and Ming records.
Debates and open questions
His motives are debated: true conquest ambition, finding land and work for his samurai, or forcing open trade with Ming.
▸Imjin War (Japanese invasions of Korea) devastated JoseonWell documented
The connection
Seven years of war killed huge numbers of Koreans, cut registered farmland to about a third of its prewar level, and destroyed palaces, records and three of the four royal archives. Tens of thousands were carried off to Japan, including skilled potters. Joseon survived but needed decades to recover.
When and how
1592–1598 across the peninsula, worst in Gyeongsang, Jeolla and around Seoul and Pyongyang; recovery lasted into the reigns of Gwanghaegun and Injo.
How we know
Land registers, the Sillok, the Jingbirok, and Korean and Japanese accounts of captives; only the Jeonju copy of the early annals survived.
Debates and open questions
The real death toll is uncertain, and the drop in registered land partly reflects lost tax records, not just ruined fields.
▸Battle of Hansan Island cut Japanese supply lines in Imjin War (Japanese invasions of Korea)Well documented
The connection
Japan planned for its fleet to sail around the southwest coast and up the Yellow Sea to supply armies pushing north. Hansan Island ended that plan; Hideyoshi then ordered his admirals to avoid battle with Yi. Konishi Yukinaga's army, stuck at Pyongyang without seaborne reinforcement, was driven out by Ming and Korean forces in early 1593.
When and how
From summer 1592 along Korea's south and west coasts; Hideyoshi's no-battle order followed within weeks of the defeat.
How we know
Hideyoshi's orders to his commanders and the Japanese halt at Pyongyang are recorded in Japanese and Korean sources.
Debates and open questions
Some historians argue Japan's supply problems came as much from guerrilla attacks and long land routes as from the naval defeats.
▸Battle of Noryang was the last major battle of Imjin War (Japanese invasions of Korea)Well documented
The connection
Noryang was fought as the Japanese, ordered home after Hideyoshi's death, were already leaving. The allied attack inflicted heavy losses on Shimazu's ships but did not stop Konishi's withdrawal. Within weeks the last Japanese troops had left Busan, ending the seven-year war.
When and how
December 16, 1598, in the Noryang strait off Namhae; the final Japanese forces sailed from Busan by the end of 1598.
How we know
Korean, Ming and Japanese sources agree on the withdrawal order and timing; Noryang is the last large engagement any of them records.
Debates and open questions
Whether attacking a departing enemy was worth Yi Sun-sin's life, and who 'won' by Japanese reckoning, is still debated.
▸Battle of Myeongnyang turned the sea war in Imjin War (Japanese invasions of Korea)Well documented
The connection
After Chilcheollyang, the Japanese navy seemed free to sail around the southwest coast to support armies pushing toward Seoul. Myeongnyang stopped that. Together with the Ming–Korean stand at Jiksan on land about ten days earlier, it pushed Japan back to fortified coastal camps in the south, where the war bogged down.
When and how
Autumn 1597 along Korea's southwest coast and in Chungcheong; Jiksan in mid-October, Myeongnyang on October 26.
How we know
Korean, Ming and Japanese records show Japanese forces falling back to coastal forts (waeseong) after these battles.
Debates and open questions
Japanese historians often present the pullback as a planned winter retreat rather than a defeat, so the battle's strategic weight is debated.
▸Righteous armies (uibyeong) of the Imjin War resisted Japanese forces in Imjin War (Japanese invasions of Korea)Well documented
The connection
With the regular army broken in the first weeks, righteous armies raided Japanese supply lines, retook towns and helped defend key points such as Jinju in 1592. Gwak Jae-u's forces kept the Japanese out of western Gyeongsang, shielding the Jeolla rice region. Many militias were later folded into the government army.
When and how
1592–1598 across southern and central Korea; leaders included Gwak Jae-u, Go Gyeong-myeong, Jo Heon, Kim Cheon-il and the monks Hyujeong and Yujeong.
How we know
Korean court records, leaders' diaries, and Japanese reports complaining of constant attacks in occupied areas.
Debates and open questions
Their military weight compared with the navy and Ming armies is debated; local pride may have inflated some accounts.
▸Imjin War (Japanese invasions of Korea) drained Ming, setting the stage for Manchu invasions of KoreaMostly agreed
The connection
Ming China spent huge sums and sent large armies to save Joseon, straining its treasury and pulling troops from its northeast frontier. Meanwhile Nurhaci was uniting the Jurchen tribes of Manchuria; he founded Later Jin in 1616 and beat Ming at Sarhu in 1619. Joseon, grateful to Ming for 'restoring the nation,' was caught between them.
When and how
1592–1619 in Ming China, Manchuria and Korea; a Joseon contingent fought on the losing Ming side at Sarhu in 1619.
How sure are we?
Ming fiscal records and court debates show heavy Korea war costs; Chinese and Korean sources record Nurhaci's rise in the same years.
Debates and open questions
How much the Korean war, versus other Ming troubles like frontier wars, court infighting and revolts, weakened Ming is debated.
▸Gwanghaegun rebuilt after Imjin War (Japanese invasions of Korea)Well documented
The connection
As crown prince, Gwanghaegun ran a branch court that rallied troops during the war. As king he rebuilt Changdeokgung and other palaces, began the Daedong law, which replaced tribute in local goods with a rice tax and eased farmers' burdens, and published the Dongui bogam to restore medical care.
When and how
1592–1623; the branch court operated in the north and east during the war; reconstruction followed in Hanyang (Seoul) with officials like Yi Won-ik and physician Heo Jun.
How we know
The Gwanghaegun ilgi, though written by his enemies, records the rebuilding, the Daedong law and the medical publications.
Debates and open questions
His costly palace building was one charge against him; whether it was needed reconstruction or extravagance is debated.