The Battle of Inchon (), also spelled Battle of Incheon, was an amphibious invasion and a battle of the Korean War that resulted in a decisive victory and strategic reversal in favor of the United Nations Command (UN). The operation involved some 75,000 troops and 261 naval vessels and led to the recapture of the South Korean capital of Seoul two weeks later. The code name for the Inchon operation was Operation Chromite.
The battle began on 15 September 1950 and ended on 19 September. Through a surprise amphibious assault far from the Pusan Perimeter that UN and Republic of Korea Army (ROK) forces were desperately defending, the largely undefended city of Incheon was secured after being bombed by UN forces. The battle ended a string of victories by the North Korean Korean People's Army (KPA). The subsequent UN recapture of Seoul partially severed the KPA's supply lines in South Korea.
The UN and ROK forces were commanded by General of the Army Douglas MacArthur of the United States Army. MacArthur was the driving force behind the operation, overcoming the strong misgivings of more cautious generals to a risky assault over extremely unfavorable terrain. The battle was followed by a rapid collapse of the KPA; within a month of the Incheon landing, the Americans had taken 135,000 KPA troops prisoner.
Background
Pusan Perimeter
From the outbreak of the Korean War following the invasion of South Korea by North Korea on 25 June 1950, the KPA had enjoyed superiority in both manpower and ground combat equipment over the ROK and UN forces dispatched to South Korea to prevent it from collapsing. The North Korean strategy was to aggressively pursue UN and ROK forces on all avenues of approach south and to engage them, attacking from the front and initiating a double envelopment of both flanks of the defending units, which allowed the KPA to surround and cut off the opposing force, forcing it to retreat in disarray. From their initial 25 June offensive to fighting in July and early August, the KPA used this tactic to defeat the UN forces they encountered and push southward. However, with the establishment of the Pusan Perimeter in August, UN forces held a continuous line which the KPA could not flank. The KPA advantages in numbers decreased daily as the superior UN logistical system brought in more troops and supplies to the UN forces.
When the KPA approached the Pusan Perimeter on 5 August, they attempted the same frontal assault technique on the four main avenues of approach into the perimeter. Throughout August, they conducted direct assaults resulting in the Battle of Masan, the Battle of Battle Mountain, the First Battle of Naktong Bulge, the Battle of Taegu, and the Battle of the Bowling Alley. On the east coast of the Korean Peninsula, the ROK repulsed three KPA divisions at the Battle of P'ohang-dong. The KPA attacks stalled as UN forces repelled the attack. All along the front, the KPA reeled from these defeats, the first time in the war North Korean tactics had failed.
By the end of August the KPA had been pushed beyond their limits and many of the original units were at far reduced strength and effectiveness. Logistic problems wracked the KPA, and shortages of food, weapons, equipment and replacement soldiers proved devastating for their units. However, the KPA retained high morale and enough supply to allow for another large-scale offensive. On 1 September the KPA threw their entire military into one final bid to break the Pusan Perimeter, the Great Naktong Offensive, a five-pronged simultaneous attack across the entire perimeter. The attack caught UN forces by surprise and almost overwhelmed them. KPA troops attacked Kyongju, surrounded Taegu and Ka-san, recrossed the Naktong Bulge, threatened Yongsan, and continued their attack at Masan, focusing on Nam River and Haman. However, despite their efforts, in one of the most brutal fights of the Korean War, the KPA were unsuccessful. Unable to hold their gains, the KPA retreated from the offensive a much weaker force, and vulnerable to counterattack.