Convinced that the U.S., and the United Nations would not defend South Korea, the North Koreans crossed the lightly defended 38th parallel at dawn on June 25, 1950 with tanks and infantry in an unprovoked act of aggression and in open defiance of the United Nations. The North Korean plan was advance at a rate of 32 kilometers a day and take all of South Korea in a month.

The South Koreans sometimes refer to the war as the “6–25 War” because it began on June 25. They had done little reconnaissance or intelligence work and were totally unprepared. The South Korean defenses were minimal: consisting of small bodies of troops in scattered outpost with roving patrols. There was no massing of soldiers. The air force of 24 trainers provided no support. They also were seriously lacking tanks and heavy artillery.

North Korean divisions backed by Soviet-made T-34 tanks moved easily southward. Kaesong — near the 38th parallel and now part of North Korea — was taken in 5½ hours. Seoul, located about 40 kilometers (25 miles) from the border, fell in three days. Within several weeks North Korea controlled four fifths of the South Korea and the South Korean and American armies had been pushed all the way to Pusan at the southeastern corner of the Korean peninsula. North Korea might have won the war if they had captured Pusan before reinforcements arrived three months later.

North Koreans at the historical museum north of Panmunjon claim that Americans in the south mounted the first attack of the Korean War. When asked how North Korean forces could reach Seoul in only three days after the beginning of the war, officials at the museum said that their ability to repel the American invasion and mount a counter-offensive so quickly was proof of their military skill.

The June 1950 invasion following a year and a half of sporadic fighting throughout Korea but primarily in the south between pro-communist and anti-communist factions. North Korea proclaimed that the war was for national liberation and unification of the peninsula. [Source: “Worldmark Encyclopedia of Nations”, Thomson Gale, 2007]

North Korea Prepares for War

In early 1950, North Korean leader Kim Il-sung traveled to Moscow for a meeting with Stalin. They discussed Kim’s plans to invade the South, and Kim asked what Soviet assistance could be expected. Stalin advised him to discuss the invasion plan with Mao Zedong, who also happened to be in Moscow. After discussions, Mao agreed that the South was weak enough to be conquered, and Stalin also approved the invasion. [Source: “Two Strategic Intelligence Mistakes in Korea, 1950" by P. K. Rose, CIA, Center for the Study of Intelligence, CSI Publications, Studies in Intelligence Studies, fall-winter 2001]

By the spring of 1950, North Korea’s preparations for war had become readily recognizable. Monthly CIA reports describe the military buildup of DPRK forces, but also discount the possibility of an actual invasion. It was believed that DPRK forces could not mount a successful attack without Soviet assistance, and such assistance would indicate a worldwide Communist offensive. There were no indications in Europe that such an offensive was in preparation. On 10 May, the South Korean Defense Ministry publicly warned at a press conference that DPRK troops were massing at the border and there was danger of an invasion.

Throughout June, intelligence reports from South Korea and the CIA provide clear descriptions of DPRK preparations for war. These reports noted the removal of civilians from the border area, the restriction of all transport capabilities for military use only, and the movements of infantry and armor units to the border area. Also, following classic Communist political tactics, the DPRK began an international propaganda campaign against the ROK “police state.” 0n 6 June, CIA reported another interesting international development: all East Asian senior Soviet diplomats were recalled to Moscow for consultations. The CIA believed the purpose of the recall was to develop a new plan to counter anti-Communist efforts in the region.

On 20 June 1950, the CIA published a report, based primarily on human assets, concluding that the DPRK had the capability to invade the South at any time. President Truman, Secretary of State Acheson, and Secretary of Defense Johnson all received copies of this report. Five days later, at fouram, the DRPK invaded the South. Both Washington and the FEC in Tokyo were surprised and unprepared. On 30 June 1950, President Truman authorized the use of US ground forces in Korea.

North Korean Advance into South Korea

After launching their attack in June 1950, North Korean forces fought their way south through Seoul. South Korean resistance collapsed as the roads south of Seoul became blocked with refugees, who were fleeing North Korean columns spearheaded with tanks supplied by the Soviet Union. Task Force Smith, the first United States troops to enter the war, made a futile stand at Suwon, a town some 48 kilometers (30 miles) south of Seoul.

When North Korea invaded South Korea the poor quality of the South Korean armed forces immediately became apparent. Although South Korea had 94,000 troops when North Korea began its all-out surprise attack, one week later only 20,000 troops could be accounted for. [Source: Andrea Matles Savada and William Shaw, Library of Congress, 1990*]

The North Korean forces, larger and better equipped than their South Korean counterparts, advanced quickly, overtaking Seoul in three days. By early August, South Korean forces were confined to the Pusan-Taegu corridor in the southeastern corner of the peninsula to a territory 140 kilometers long and 90 kilometers wide. The rest of the territory was completely in the hands of the North Korean army. By September, U.S. and South Korean forces were sequestered in the area around Pusan on southeast corner of the Korean peninsula. [Source: Library of Congress, May 2005]

The United States, fearing that inaction in Korea would be interpreted as appeasement of communist aggression elsewhere in the world, was determined that South Korea should not be overwhelmed and asked the United Nations (UN) Security Council to intervene.

North Korean Military

The communists had built a formidable political and military structure in North Korea under the aegis of the Soviet command. They had created a regional Five-Province Administrative Bureau in October 1945, which was reorganized into the North Korean Provisional People's Committee in February 1946 and shed the "Provisional" component of its name twelve months later. The communists also expanded and consolidated their party's strength by merging all of the left-wing groups into the North Korean Workers' Party in August 1946. Beginning in 1946, the armed forces also were organized and reinforced. Between 1946 and 1949, large numbers of North Korean youths — at least 10,000 — were taken to the Soviet Union for military training. A draft was instituted, and in 1949 two divisions — 40,000 troops — of the former Korean Volunteer Army in China, who had trained under the Chinese communists, and had participated in the Chinese civil war (1945-49), returned to North Korea. [Source: Andrea Matles Savada and William Shaw, Library of Congress, 1990]

By June 1950, North Korean forces numbered between 150,000 and 200,000 troops, organized into ten infantry divisions, one tank division, and one air force division. Soviet equipment, including automatic weapons of various types, T-34 tanks, and Yak fighter planes, had also been pouring into North Korea in early 1950. These forces were to fight the ill-equipped South Korean army of less than 100,000 men — an army lacking in tanks, heavy artillery, and combat airplanes, plus a coast guard of 4,000 men and a police force of 45,000 men.

The events following the June 1950 invasion proved the superiority of North Korean military forces and the soundness of their overall invasion strategy. South Korea's army was simply overwhelmed; Seoul fell within three days. By early August, South Korean forces were confined in the southeastern corner of the peninsula to a territory 140 kilometers long and 90 kilometers wide. The rest of the territory was completely in the hands of the North Korean army.

Eyewitness Account of the Invasion of South Korea

Recalling the invasion of Seoul during the Korean War, H. Edward Kim wrote in National Geographic, "I was playing with my sisters on the street in front of our house in Seoul. Suddenly a siren started to wail. Loudspeakers blared, 'All military personnel report to your posts immediately. This is an emergency. I was 10 years old and didn't know what was going on. People began running. The police told us to get inside...That evening I head gunfire and windows shattering. The sky was red, streaked with smoke, as if the whole city was burning."

"Many a day and night we spent in a cellar," Kim wrote, "listening to the thud of guns around the defense perimeter, the whine and crash of shells and bombs around us. Boyish curiosity overcame prudence, and I'd poke my head out to watch dogfights overhead."

"I'll never forget the evacuation of Seoul," Kim wrote, "and the flight southward — roads clogged with vehicles, families separated in the confusion, children crying and women screaming; the hunger, the exhaustion, the terror. We were lucky. We made it together, my father and mother, six sisters and I to the southern port of Pusan, jammed in the back of a truck with several other families."

A North Korean woman defector later told the New Yorker, “My husband told me that Seoul was empty when he marched through, and he thought that was strange because he thought the U.S. and South Korea started the war. Even though he was in the military he believed that.”

First Day of the Korean War

Young Sik Kim wrote: June 25: Kim Il Sung declares war and North Korean Peoples Army invades South Korea in force. At the same time, Radio Seoul says South Korean army units are advancing rapidly towards Pyongyang and will liberate North Korea very soon. Radio Pyongyang claims major victories and widespread uprisings throughout South Korea. We are confused but want to believe the Seoul's version of what's going on and expect South Korean units to reach our town at any time. [Source: Young Sik Kim, Kim wrote this account in 1995. Born in 1935, he was the son of a rich North Korean landowner and was an anti-Communist, and worked for the Americans during and after the Korean War. Some have questioned the reliability of the account. I have removed some of the opinions and comments in the account]

The invasion starts at 4:00am on the Onjin Peninsula. North Koreans start shelling Kaesong at 5:00am. The ROK 12th Regiment panics and runs south. By 9:30am, Kaesung is in North Korean hands. Several US military advisers (KMAG) are taken captive. The main thrust is spear-headed by the North Korean Army 3rd and 4th divisions at Cholwon. The ROKA 7th Division collapses at Cholwon and the North Korean tanks race toward Seoul.

9:00am, John Muccio, the U.S. ambassador to South Korea, cables the State Dept. — "an all-out offensive against the Republic of Korea has begun" It has taken the U.S. and South Korean governments five full hours to realize what's happening.

10:00am:Washington, DC: Gen. Bradley, Chairman of the U.S. JCS, hears about the invasion from United Press reporter Dayton Moore. Bradley is stunned.The general informs his chiefs of staff — "I am of the opinion that South Korea will not fall in the present attack unless the Russians actively participate in the operation. Therefore, if Korea falls, we may want to recommend even stronger action in the case of Formosa in order to offset the effect of the fall of South Korea on the rest of East Asia."

5:00pm: Tokyo: MacArthur states "This is probably only a reconnaissance in force. If those asses back in Washington only will not hobble me, I can handle it with one arm tied behind my back." Later sends a few fighter planes to the South Korean Air Force although the South Koreans are not sure what to do with them. Around the time MacArthur makes his announcement two North Korean YAK fighters strafe Rhee's residence. Rhee is set to flee for his life. US CIC people monitoring Rhee's phone notify Muccio. Muccio warns Rhee that the entire ROK Army will quit fighting if Rhee fled Seoul now. Rhee agrees to stay in Seoul with Muccio. Muccio makes arrangements for evacuation of American civilians.

Second Day of the Korean War

Young Sik Kim wrote: June 26: 6:00am, Syngman Rhee phones MacArthur at his house. An aid tells Rhee that the general is not to be disturbed and tells Rhee to call back later in the morning. This drives Rhee into a rage: "American citizens will die one by one while you keep the general asleep in peace." Rhee demands to talk to the general now. Finally, MacArthur takes the phone and hears an enraged Rhee: "Had your country been a little more concerned about us, we would not have come to this! We've warned you many times. Now you must save Korea." MacArthur assures Rhee that he will take care of Korea. [Source: Young Sik Kim,]

June 26: 9:30am: Pyongyang: Kim Il Sung speaks to the nation: "Dear brothers and sisters! Great danger threatens our motherland and its people! What is needed to liquidate this menace? Under the banner of the Korean People's Democratic Republic, we must complete the unification of the motherland and create a single, independent, democratic state! The war which we are forced to wage is a just war for the unification and independence of the motherland and for freedom and democracy."

June 26: 11:00am: Radio Seoul (HLKA) says that the "Fierce Tiger" unit (Maengho Dae) of the 17th Regiment has liberated Haeju City on the Onjin Peninsula. It goes on to say that South Korean soldiers have killed 1,580 North Korean soldiers. Maengho Dae is led by Col. Kim Chong Won, formerly a sergeant in the Japanese Imperial Army, who fled North Korea in 1945.

US Ambassador Muccio orders evacuation of all American civilians. Some 700 Americans are loaded onto a Norwegian fertilizer ship at Inchon.. MacArthur is not worried — he believes that the ROKs will regroup and throw back the invaders. He is angry at Muccio for ordering the American evacuation. At this very moment, Muccio hears North Korean Army artillery closing on Seoul.

Later into the night, Rhee Syngman decides to flee Seoul without asking Muccio's permission. A special train is requisitioned to carry Rhee and his close associates (and their relatives). The train leaves in the dark of the night. Somehow, the American CIC fails to inform Muccio of Rhee's flight.

Third Day of the Korean War

Young Sik Kim wrote: June 27: Muccio flees Seoul. He drives his jeep south looking for the South Korean Government and Rhee. For the first time, MacArthur realizes the gravity of the Korean situation. He tells Foster Dulles "The only thing we can do is get our people safely out of the country." A courier delivers an urgent message from the Joint Chiefs of Staff. MacArthur tells the courier: "Tell them I'm engaged in seeing Ambassador Dulles off.. If I don't get back in time, have the chief of staff talk to the secretary." [Source: Young Sik Kim,]

“A general panic hits the Seoul citizens and tens of thousands of refugees clog all roads leading south. Two days earlier, the ROK army engineers placed explosives on all bridges on the Han River. There are much debates on when to blow up the bridges. Gen. Chae and the U.S. advisers want to wait — there are more than 10,000 ROK troops yet to cross the Han River — in addition to the countless refugees. The Deputy Minister of Defense orders the bridges destroyed promptly but Gen. Chae refuses — Gen. Chae is bodily removed from his command. Radio Seoul HLKA is still saying that South Korean troops are marching on to Pyongyang.

Chae was killed a few days later in a mysterious circumstance and Gen. Jung Il Kwon (a former captain in the Japanese Imperial Army) takes over and obeys the command to blow up the bridge. The chief of the South Korean Corps of Engineers blows up the Han River bridge at 2:15am and kills several hundreds soldiers and refugees still on the bridge. He cuts off the main escape route for the retreating South Korean troops and refugees. The poor engineer was executed. Kim Paik Il and the Deputy Defense Minister who issued the order were untouched.

Washington, DC: The U.S. JCS finally realizes that South Korea is about to fall without US ground troops. The much vaunted ROK Army is in full rout and there is little hope that it is about to regroup on its own. How could all those experts at the CIA and the military brass have missed their mark so badly? At a war council, Pres. Truman and Dean Acheson propose sending ground troops. Gen. Bradley opposes military intervention — "if we committed our ground forces to Korea, we would have to have a mobilization, at least a call-up of some National Guard divisions.". The meeting adjourns without any decision. The following day, Gen. Eisenhower urges the military and Pres. Truman to intervene in Korea.

US Ambassador Muccio at last finds the missing South Korean government in Taejun. Rhee is holed up in a house virtually isolated from the world around him. Muccio is angry at Rhee for fleeing Seoul without his approval and Rhee is mad at Muccio for not providing US troops.

Fourth Day of the Korean War

Young Sik Kim wrote: June 29: 8:00am: Muccio picks up Rhee Syngman to meet MacArthur at Suwon. MacArthur's plane (Bataan) is attacked by a North Korean YAK fighter, but no damage is done. Rhee meets with MacArthur in private for two and half hours. No one knows what they have discussed. Big Mac states — "Give me two American divisions and I can hold Korea." Upon completion of the secret meeting, Rhee and Muccio head back to Taejun. Their plane narrowly escapes from another YAK fighter. [Source: Young Sik Kim,]

June 29: North Korean Army takes Seoul — It is weird. We see pictures of North Korean soldiers marching in Seoul and yet Seoul Radio is still claiming some fantastic victories!! How can this be?...At last the sad truth emerges. A column of South Korean POW's passes through our town. Some are wounded and being carried by fellow POWs. The column is lead by a South Korean army officer still proud with his head held high. But the rest seem to be dejected and scared. Two women from the crowd throw rocks at the column. A North Korean army officer runs toward the women shouting something and the women run away. The crowd is quiet and sad. Some people are crying openly.

June 29: Washington: Dulles reports to Truman on the confused status of MacArthur and advises Truman to fire MacArthur now. But Truman is scared of MacArthur, who "is involved politically in this country and he cannot be recalled without causing a tremendous reaction. He has been built up to heroic stature." Dulles agrees with Truman, but promises his full support if Truman decided to fire MacArthur in the future.

Fifth Day of the Korean War

Young Sik Kim wrote: June 30: Kim Kyu Sik welcomes the Korea People's Army. Kim was one of the founding fathers of the Korean Provisional Government (KPG) in China. He was named its foreign minister in 1919 and he went to Paris (Treaty of Versailles) to petition for Korean independence — in vain.... Gen. Song Ho Song, former commander of the ROK 2nd Division, organizes the People's Volunteer Army manned by South Koreans. [Source: Young Sik Kim,]

The U.S. CIA reported: "The ROK government's past failure to win the support of its restless student class could account for more than half of Seoul's students actively aiding the Communist invaders, with many voluntarily enlisting in the Northern army. Apparently attracted by the glamour of a winning army, the morale of these recruits may suffer rapidly if the going gets rough...The working class generally supports the Northern Koreans, while merchants are neutral and the intelligentsia continue to be pro-Southern...The streets are crowded, especially with youths engaging in Communist demonstrations."

I am bewildered by the easy victory over the South Korean Army. Newspapers are full of combat stories: South Koreans trying to stop tanks with hand grenades; South Koreans surrendering at the sight of a tank; South Korean soldiers turning against their own officers and so on.

MacArther reports to Washington: "The only assurance of holding the present line, and the ability to regain later lost ground, is through the introduction of US ground forces into the Korean battle area." The Army Chief of Staff (Gen. Collins), is taken in by MacArthur (and earlier by Ike) and changes his mind about not sending troops to Korea. Earlier MacArthur was given the authority to send a regimental combat team to Pusan to safeguard it for evacuation of US citizens. However, MacArthur wants Gen. Collin's approval to send one or two regimentals teams to the front lines. Collins goes over Bradley's head and gets Truman's approval and tells MacArthur: "Your recommendation to move one regimental combat team to combat area is approved."

A CIA recommendation for military intervention in Korea reads: "Voluntary or forced withdrawal would be a calamity. US commitments abroad no longer would be trusted. Friendly nations might lose political control or feel compelled to seek an accommodation with the USSR. The USSR will proceed with limited aggressions. It would be politically and psychologically more advantageous for the U.S. to mobilize in support of US and U.N. intervention in Korea rather than to mobilize after a withdrawal."

5,000 South Koreans executed to stop collaboration

South Korean soldiers executed nearly 5,000 people during the early months of the Korean War to stop them collaborating with invading communist troops, a government commission has said. AFP reported: The victims were members of the National Guidance League, who were being "re-educated" to eliminate their left-wing sympathies and others suspected of communist leanings. Historians say officials met membership quotas by pressuring peasants into signing up with promises of rice rations or other benefits, with more than 300,000 people on the league's rolls. [Source: The Telegraph, AFP, 26 Nov 2009]

“The Truth and Reconciliation Commission said it has confirmed that South Korean troops and police rounded up and executed at least 4,934 league members between June and September of 1950, as North Korean invaders pushed down the peninsula. The findings marked the first specific number of confirmed deaths in the incident. "The government of then-president Syngman Rhee was in a state of panic at the start of the war and deeply worried that Bodo League members could sympathise with North Korea and become a threat to the government," the commission said in a statement. Since 2005, the commission has investigated civilian executions and other past human rights violations.

“The commission said it believes the executions were perpetrated based on "decisions and orders" from the "highest level" of the government, since troops, police and other state agencies were mobilised in a swift and organised manner for the killings. The mass executions represent one of the darkest chapters of the Korean War, but were largely hidden from history for decades under a series of military-backed authoritarian governments after the war. South Korea became fully democratic in the late 1980s. The commission recommended that the government offer an official apology, come up with legal and other measures to prevent a repeat of the slaughter, and enact legislation to compensate the victims.”

Refugees and Families Divided by the Korean War

The Korean War produced millions of refugees. Edward Daily, a soldier just off the ship from Japan in the early weeks of the war told Associated Press:“Thousands of refugees were fleeing south. With so many refugees mixing with GIs, trucks and equipment, the roads became jammed and impassable. Being surrounded by so many Koreans made us a little jumpy. Reports had filtered down that North Korea regulars were masquerading as civilians, donning the traditional white clothing worn by peasants. It was impossible to tell friend from foe.”

By one estimate 10 million families were broken up by the Korean War. One North Korean man who became divided from his family and ended up in South Korea because he attended his school graduation told the New York Times: “My mother had to go to church that day and couldn’t attend the ceremony, an my father was working for the railroad and couldn’t come. So I told my parents goodby, intending to return after the ceremony.” He eventually became a prisoner of war and didn’t see his family again until 50 years later.

A South Korean woman told the Independent, she lost track of her son who had gone to check out what had been going on in the battle zone, “He went out that day without telling me. I was out at the time, and he said to his brother, ‘I’m going to take a look at school. Tell Mum.’ If I’d been there, I’d have told him not to go. He was 16 years old.”

A woman said her mother was arrested by North Korean Communists because she was a capitalist. “My uncle, who was in the army, moved into our house and refused to give us any food, even though we begged him to just give us a little something for my baby brothers.” Realizing that they would probably die, their older sisters moved them to the south.

Eliot A. Cohen wrote in the Washington Post: “one may follow the moral tide of an conflict by following the streams of refugees, When the communists took over in the North, two million fled south. And as the battles seesawed back and forth over the peninsula in 1950, hundreds of thousands if not millions more fled the advancing communist forces by heading toward South Korean and American lines. At war’s end , one of the biggest problems was what to do with the tens of thousands of prisoners of war who were desperate not to return to North Korea or to China.”

In some cases American units were ordered to machine gun swarms of refugees, with some communists mixed, who overran their positions.

Image Sources: Wikimedia Commons.

Text Sources: South Korean government websites, Korea Tourism Organization, Cultural Heritage Administration, Republic of Korea, UNESCO, Wikipedia, Library of Congress, CIA World Factbook, World Bank, Lonely Planet guides, New York Times, Washington Post, Los Angeles Times, National Geographic, Smithsonian magazine, The New Yorker, “Culture and Customs of Korea” by Donald N. Clark, Chunghee Sarah Soh in “Countries and Their Cultures”, “Columbia Encyclopedia”, Korea Times, Korea Herald, The Hankyoreh, JoongAng Daily, Radio Free Asia, Bloomberg, Reuters, Associated Press, BBC, AFP, The Atlantic, Yomiuri Shimbun, The Guardian and various books and other publications.

Updated in July 2021

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