Battles & Wars › Gunpowder empires › Admiral Yi Sun-sin
Battle of Hansan Island
August 14, 1592· Battle· Asia & Pacific
Well documentedSolid records, physical evidence or scientific consensus.
Admiral Yi Sun-sin lured a Japanese fleet into open water and destroyed most of it in a crane-wing encirclement.
See it on the Battles & Wars map →What happened
In August 1592 the Japanese commander Wakisaka Yasuharu's fleet of about 73 ships anchored in the narrow Gyeonnaeryang strait. Yi, with about 55 Korean ships, sent a few vessels in as bait, then feigned retreat toward Hansan Island (한산도). In open water his ships swung into a half-circle, the 'crane's wing', and pounded the Japanese with cannon. Korean reports say 47 Japanese ships were sunk and 12 captured; Wakisaka escaped.
Why it matters
It broke Japanese naval power in the south, protected Jeolla Province and stopped Japan from supplying its armies by sea, a turning point of the war.
How we know
Yi's report to King Seonjo and his war diary, Ryu Seong-ryong's Jingbirok, and Japanese accounts of the Wakisaka family. The Jeseungdang shrine on Hansan Island marks Yi's base.
Still debated
Japanese losses rest mainly on Korean reports, and how the crane formation was handled under oars is reconstructed rather than recorded in detail.
Connections (3)
▸Admiral Yi Sun-sin won Battle of Hansan IslandWell documented
The connection
Hansan showed Yi's method. Judging the Gyeonnaeryang strait, where Wakisaka Yasuharu's fleet lay, too narrow and rocky for his heavy panokseon warships, he lured the enemy into open water. There he kept his distance and let Korean cannon do the work, denying the Japanese, who relied on boarding, a chance to fight hand to hand.
When and how
Waters between Geoje and Hansan islands, off Tongyeong, August 14, 1592; Yi with fellow commanders Yi Eok-gi and Won Gyun.
How we know
Yi's own battle report to King Seonjo and his war diary describe the plan, and Japanese records of the Wakisaka family confirm the defeat.
Debates and open questions
How far the crane's wing was Yi's own idea rather than an existing formation adapted to the sea is unclear, and details rely mostly on Korean sources.
▸Battle of Hansan Island cut Japan's sea supply in Imjin War (Japanese invasions of Korea)Well documented
The connection
Japan's plan relied on shipping troops and supplies around Korea's south and west coasts to its army at Pyongyang for the march into China. After Hansan, Hideyoshi ordered his admirals to avoid battle with Yi. Without sea supply, Konishi Yukinaga's army at Pyongyang stalled, giving Korean guerrillas and Ming armies time to counterattack in early 1593.
When and how
Korea's south coast, summer 1592; the Japanese army under Konishi Yukinaga waiting at Pyongyang; Hideyoshi directing the war from Japan.
How we know
Hideyoshi's orders forbidding his navy to engage survive, and Ryu Seong-ryong's Jingbirok links the naval defeats directly to Japan's stalled advance.
Debates and open questions
Some historians argue Japan's land advance would have stalled anyway from guerrilla attacks, winter and Ming intervention; Hansan's exact weight is debated.
▸Korean turtle ship (geobukseon) fought in Yi's victory at Battle of Hansan IslandWell documented
The connection
At Hansan Island Yi lured the Japanese fleet into open water, then wrapped it in his crane's-wing formation. Turtle ships, safe from boarding, charged into the enemy and fired cannon at close range, while panokseon pounded from the arc. Korean reports say 47 Japanese ships were sunk and 12 captured.
When and how
Waters off Hansan Island, near Tongyeong on Korea's south coast, August 14, 1592; Yi Sun-sin against Wakisaka Yasuharu.
How we know
Yi's official report to the court describes turtle ships leading the attack, and Japanese accounts confirm Wakisaka's defeat.
Debates and open questions
How many turtle ships fought, perhaps two or three, and how large their role was compared with the panokseon is debated.