Korean War: Inchon Landings

Inchon Invasion
United Nations Fleet off Inchon, September 15, 1950.

National Air and Space Museum

 

The Inchon landings took place on September 15, 1950, during the Korean War (1950-1953). Since the beginning of the conflict that June, South Korean and United Nations forces had been steadily driven south into a tight perimeter around the port of Pusan. Seeking to regain the initiative and liberate the South Korean capital of Seoul, General Douglas MacArthur devised a plan for a daring amphibious landing at Inchon on South Korea's west coast. Far from the Pusan Perimeter, his troops began landing on September 15 and caught the North Koreans by surprise. The landings, coupled with an offensive from the Pusan Perimeter, caused the North Koreans to retreat back across the 38th Parallel with UN forces in pursuit.

Fast Facts: Inchon Invasion

  • Conflict: Korean War (1950-1953)
  • Dates: September 15, 1950
  • Armies & Commanders:
  • Casualties:
    • United Nations: 566 killed and 2,713 wounded
    • North Korea: 35,000 killed and captured

Background

Following the opening of the Korean War and the North Korean invasion of South Korea in the summer of 1950, United Nations forces were steadily driven south from the 38th Parallel. Initially lacking the necessary equipment to halt the North Korean armor, American troops suffered defeats at Pyongtaek, Chonan, and Chochiwon before attempting to make a stand at Taejeon. Though the city ultimately fell after several days of fighting, the effort made American and South Korean forces bought valuable time for additional men and material to be brought to the peninsula as well as for UN troops to establish a defensive line in the southeast which was dubbed the Pusan Perimeter.

MacArthur at Inchon
General Douglas MacArthur during the Inchon Landings, September 1950. National Archives and Records Administration

Protecting the critical port of Pusan, this line came under repeated attacks by the North Koreans. With the bulk of the North Korean People's Army (NKPA) engaged around Pusan, UN Supreme Commander General Douglas MacArthur began advocating for a daring amphibious strike on the peninsula's west coast at Inchon. This he argued would catch the NKPA off guard, while landing UN troops close to the capital at Seoul and placing them in a position to cut the North Korean's supply lines.

Many were initially skeptical of MacArthur's plan as Inchon's harbor possessed a narrow approach channel, strong current, and wildly fluctuating tides. Also, the harbor was surrounded by easily defended seawalls. In presenting his plan, Operation Chromite, MacArthur cited these factors as reasons the NKPA would not anticipate an attack at Inchon. After finally winning approval from Washington, MacArthur selected the US Marines to lead the attack. Ravaged by post-World War II cutbacks, the Marines consolidated all available manpower and reactivated aging equipment to prepare for the landings.

Pre-Invasion Operations

To pave the way for the invasion, Operation Trudy Jackson was launched a week before the landings. This involved the landing of a joint CIA-military intelligence team on Yonghung-do Island in the Flying Fish Channel on the approach to Inchon. Led by Navy Lieutenant Eugene Clark, this team provided intelligence to UN forces and restarted the lighthouse at Palmi-do. Aided by South Korean counter-intelligence officer Colonel Ke In-Ju, Clark's team collected important data regarding the proposed landing beaches, defenses, and local tides.

This latter piece of information proved critical as they found that the American tidal charts for the area were inaccurate. When Clark's activities were discovered, the North Koreans dispatched a patrol boat and later several armed junks to investigate. After mounting a machine gun on a sampan, Clark's men were able to sink the patrol boat drive off the enemy. As retribution, the NKPA killed 50 civilians for aiding Clark.

Preparations

As the invasion fleet neared, UN aircraft began striking a variety of targets around Inchon. Some of these were provided by the fast carriers of Task Force 77, USS Philippine Sea (CV-47), USS Valley Forge (CV-45), and USS Boxer (CV-21), which assumed a position offshore. On September 13, UN cruisers and destroyers closed on Inchon to clear mines from the Flying Fish Channel and to shell NKPA positions on Wolmi-do Island in Inchon harbor. Though these actions caused the North Koreans to believe than an invasion was coming, the commander at Wolmi-do assured the NKPA command that he could repulse any attack. The next day, UN warships returned to Inchon and continued their bombardment.

USS Valley Forge - CV-45
USS Valley Forge (CV-45), 1948. US Naval History & Heritage Command

Going Ashore

On the morning of September 15, 1950, the invasion fleet, led by Normandy and Leyte Gulf veteran Admiral Arthur Dewey Struble, moved into position and the men of Major General Edward Almond's X Corps prepared to land. Around 6:30 AM, the first UN troops, led by Lieutenant Colonel Robert Taplett's 3rd Battalion, 5th Marines came ashore at Green Beach on the northern side of Wolmi-do. Supported by nine M26 Pershing tanks from the 1st Tank Battalion, the Marines succeeded in capturing the island by noon, suffering only 14 casualties in the process.

Inchon Landings
First Lieutenant Baldomero Lopez, USMC, leads the 3rd Platoon, Company A, 1st Battalion, 5th Marines over the seawall on the northern side of Red Beach, as the second assault wave lands at Inchon, 15 September 1950. US Naval History and Heritage Command

Through the afternoon they defended the causeway to Inchon proper, while awaiting reinforcements. Due to the extreme tides in the harbor, the second wave did not arrive until 5:30 PM. At 5:31, the first Marines landed and scaled the sea wall at Red Beach. Though under fire from North Korean positions on Cemetery and Observation Hills, the troops successfully landed and pushed inland. Located just north of the Wolmi-do causeway, the Marines on Red Beach quickly reduced the NKPA opposition, allowing forces from Green Beach to enter the battle.

Chesty Puller
Colonel Lewis "Chesty" Puller. November 1950. US Marine Corps

Pressing into Inchon, the forces from Green and Red Beaches were able to take the city and compelled the NKPA defenders to surrender. As these events were unfolding, the 1st Marine Regiment, under Colonel Lewis "Chesty" Puller was landing on "Blue Beach" to the south. Though one LST was sunk while approaching the beach, the Marines met little opposition once ashore and quickly moved to help consolidate the UN position. The landings at Inchon caught the NKPA command by surprise. Believing that the main invasion would come at Kusan (the result of UN disinformation), the NKPA only sent a small force to the area.

Aftermath & Impact

UN casualties during the Inchon landings and subsequent battle for the city were 566 killed and 2,713 wounded. In the fighting the NKPA lost more than 35,000 killed and captured. As additional UN forces came ashore, they were organized into the US X Corps. Attacking inland, they advanced towards Seoul, which was taken on September 25, after brutal house-to-house fighting.

Map of Inchon Invasion and Pusan Perimeter Breakout
United Nations Offensive, South Korea 1950 - Situation 26 September and Operations Since 15 September. US Army

The daring landing at Inchon, coupled with 8th Army's breakout from the Pusan Perimeter, threw the NKPA into a headlong retreat. UN troops quickly recovered South Korea and pressed into the north. This advance continued until late November when Chinese troops poured into North Korea causing UN forces to withdraw south.