Battles & Wars › Cold War › Korean War
Battle of Incheon (Inchon landing)
September 15, 1950· Battle· Asia & Pacific
Well documentedSolid records, physical evidence or scientific consensus.
A daring US-led amphibious landing behind North Korean lines that recaptured Seoul and turned the Korean War around.
See it on the Battles & Wars map →What happened
By September 1950 UN forces were penned into the Pusan Perimeter, a small corner of southeast Korea. MacArthur proposed landing at Incheon, Seoul's port, far behind enemy lines. Planners objected: tides there swing about 10 meters, leaving wide mudflats and only a few hours a day to land. On September 15 about 75,000 troops and some 260 ships went in. Losses were light, Seoul was retaken by September 28, and the North Korean army collapsed.
Why it matters
It cut North Korean supply lines and turned near-defeat into a UN push north, a reversal that in turn provoked China's intervention.
How we know
US Navy and Marine Corps operational records, memoirs of MacArthur and his planners, North Korean prisoner accounts and detailed official histories.
Still debated
Historians debate whether its success was brilliance or luck, given weak North Korean defenses, and whether it fed MacArthur's later overconfidence.
Connections (3)
▸Douglas MacArthur planned Battle of Incheon (Inchon landing)Well documented
The connection
MacArthur conceived the Incheon landing in the war's first weeks and pushed it through over objections from Navy planners and the Joint Chiefs, who feared the extreme tides and narrow channel. He argued surprise would come precisely because the site seemed impossible, and watched the landing from the command ship USS Mount McKinley.
When and how
Tokyo, where MacArthur had his headquarters, July–August 1950, including a decisive briefing on August 23; the landing itself on September 15, 1950.
How we know
Joint Chiefs' cables, meeting records and MacArthur's memoir Reminiscences document his role; participants confirm he won over doubters at the August 23 briefing.
Debates and open questions
How much credit belongs to staff planners and Navy officers rather than MacArthur himself is debated.
▸Battle of Incheon (Inchon landing) reversed the course of Korean WarWell documented
The connection
Landing behind North Korean lines cut the invaders' supply routes just as UN forces broke out of the Pusan Perimeter. Within two weeks Seoul was retaken and the North Korean army was shattered. The UN then crossed the 38th parallel to unify Korea, which drew China into the war.
When and how
Incheon and Seoul, September 15–28, 1950; UN forces crossed the 38th parallel in early October 1950.
How we know
Military records on both sides document the North Korean collapse after the landing and the decision to cross the parallel.
Debates and open questions
Some historians argue the breakout from Pusan would have succeeded anyway, making Incheon less decisive than its fame suggests.
▸Battle of Incheon (Inchon landing) drew UN forces north toward Battle of Chosin ReservoirWell documented
The connection
Incheon's success made UN commanders confident. Many of the same Marines who landed at Incheon were shipped around to Korea's east coast and sent north toward the Yalu River border. Spread thin across mountains in winter, they met massive Chinese forces at Chosin.
When and how
The 1st Marine Division, part of the Army's X Corps under General Edward Almond, moved from Incheon to the east coast in October 1950 and advanced inland in November.
How we know
Unit records trace the 1st Marine Division from Incheon to Wonsan and Chosin; the operational link is fully documented.
Debates and open questions
Whether overconfidence after Incheon or poor intelligence did more to expose UN forces at Chosin is debated.