After World War II, US occupation troops in Korea were stationed south of the 38th parallel, while Soviets occupied Korea north of that line.
Elections were held in South Korea despite Soviet refusal to allow elections in the North. The Republic of Korea (ROK) was proclaimed south of the 38th parallel, while north of the line became the People’s Democratic Republic of Korea. Both sides claimed they were the only legitimate government of Korea.
On June 25, North Koreans equipped with Soviet tanks and fighter planes attacked ROK forces across the 38th parallel. The United Nations Security Council demanded that the Communists withdraw across the 38th Parallel, but the North Koreans continued to advance towards Seoul. Pres. Harry Truman ordered US forces to help defend South Korea as part of the United Nations coalition.
A battalion of the US 24th Division was flown from Japan, and for sixteen days they stubbornly retreated under pressure from the North Korean onslaught. Lt. Gen. Walton H. Walker was named commander of the Eighth Army in Korea, while General Douglas MacArthur was named Supreme Commander of UN forces in the Far East.
Eighth Army and South Korean forces retreated into the Pusan perimeter, (an area 75 miles long by 50 miles wide) at the extreme southeast corner of Korea. Gen. Walker shuttled his men from one trouble spot to another throughout the perimeter in a desperate bid to halt the North Korean attacks.
The North Koreans mounted a major offensive against the Pusan perimeter and captured Pohang, but the offensive soon stalled. On September 15 the US Xth Corps, including the 1st Marines, made a surprise landing at Inchon and quickly recaptured Seoul. The Eighth Army broke out of the Pusan perimeter and moved north, linking up with the US forces moving south from Seoul.
UN forces crossed the 38th parallel as the North Koreans retreated beyond Pyongyang. China, which had warned the United Nations troops not to advance beyond the 38th Parallel, began slipping large numbers of Chinese soldiers into Korea.
Gen. MacArthur stated his intention of ending the war by Christmas. United Nation’s forces had just reached the Yalu River when four Chinese armies attacked in overwhelming force and split the Eighth Army from X Corps.
In freezing weather, 20,000 Marines and soldiers of X Corps, along with British Royal Marines and South Korean troops, began a fighting withdrawal from the Chosin Reservoir towards the port city of Hungnam, where U.S. Navy ships evacuated more than 205,000 soldiers and Korean civilians. The Eighth Army also fell back under the relentless attacks. Pyongyang was soon abandoned, and the United Nation’s forces retreated to the defenses around Seoul. Matthew Ridgway took over as commander of the Eighth Army after Gen. Walker was killed in a jeep accident.
JANUARY. United Nations forces abandoned Seoul and retreated 25 miles south in the face of an offensive by 500,000 North Koreans and Chinese. The Chinese however, had stretched their supply line to the limit, and their offensive soon ran out of steam.
FEBRUARY. Gen. Ridgway ordered I Corps to begin an attack which drove the Chinese across the Han River. The Chinese mounted several unsuccessful human-wave attacks against X Corps.
MARCH. United Nations forces recaptured Seoul, and the North Koreans were pushed north of the 38th parallel.
APRIL. President Harry Truman dismissed General MacArthur because of MacArthur’s public and repeated criticism of Truman’s war policy. Matthew Ridgway was named Supreme Commander, and General James Van Fleet took over as Eighth Army commander. The Chinese mounted yet another major offensive, but the attack was halted north of Seoul.
MAY. A Chinese corps attacked the Eighth Army and was decimated.
JUNE. The Soviets proposed a cease-fire, and Gen. Ridgway called for a meeting between military leaders to establish a truce.
JULY. Negotiations began at Kaesong, but fighting continued as both sides sought to straighten out their lines and consolidate their positions.
SEPTEMBER. Helicopters were first used in a combat zone to evacuate casualties and ferry assault troops and supplies.
NOVEMBER. Formal peace talks were established at Panmunjom.
JANUARY. Communist negotiators rejected a United Nations proposal that prisoners of war be allowed to decide if they wanted to be exchanged.
MAY. Communist prisoners of war rioted on Koje Island, capturing the American general in charge of the prison camp.
OCTOBER. Talks broke off over the issue of repatriation of prisoners.
MARCH. The Communists accepted a modified UN proposal regarding the exchange of prisoners of war.
APRIL. Talks at Panmunjom resumed, and sick and wounded prisoners were exchanged.
JULY. A finalized armistice agreement called for a 2.5 mile demilitarized zone along the front. All fighting officially ended at 10 PM on July 27, 1953.