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Korean War overview

The Korean War began with North Korea's invasion of South Korea in 1950. The conflict saw shifts in power, with both sides gaining and losing territory. The war involved major world powers, with the U.S. supporting South Korea and the Soviet Union and China backing North Korea. Despite the bloody conflict, the war ended in 1953 with an armistice, not a peace treaty, leaving North and South Korea technically still at war. Created by Sal Khan.

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  • aqualine tree style avatar for user V Ananya
    Why is the border between North Korea and South Korea called the '38th Parallel'? Is it a reference to something?
    (16 votes)
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  • blobby green style avatar for user monsuco
    South Korea and North Korea both began as dictatorships. I'm well aware of South Korea being one of the 4 "Asian Tiger" nations as it, along with Taiwan, Singapore and Hong Kong rapidly transitioned from poverty to prosperity by rapidly adopting capitalism.

    My question is how did South Korea end up becoming a liberal democracy like it is today? Was it sort of like Chile where adopting free markets gradually brought in ideas about other kinds of freedom or was there some sort of revolt?
    (12 votes)
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    • spunky sam green style avatar for user History Helper
      The Republic of Korea's (South Korea) approach to democracy was very gradual. After the Korean War, the Rhee administration was autocratic and weak. This led to people (majority of them were university students) to protest, and overthrow the Rhee government. Then, Yoon Bo-sun was elected president. But Yoon was overthrown by a military general named Park Chung-hee by a coup. South Korea was once again in a dictatorship, but in a good one. Park Chung-hee's legacy is very controversial in Korea today, but most agree that it was he that made what we know as South Korea today. He actually promoted capitalism by planning massive exports, and supporting large businesses (Samsung, Hyundai, and etc.) ran by conglomerates. He has violated several human rights (censorship, collectivism, and etc.), but his economic legacy is draws mixed reaction from Korea. But later Park was assassinated, and Choi Kyu-ha was democratically elected, but his power wouldn't last long. Another general named Chun Doo-hwan launched a coup and became a dictator. Under his rule, South Korea became the fastest growing economy in the world. But his despotism is what makes him controversial like Park. Anyway, in 1988, there was a large pro-democracy movement in Korea, and Chun agreed to leave office voluntarily. Then finally, South Korea finally became a democratic republic under a new constitution.
      (23 votes)
  • mr pink red style avatar for user Daniel Van Horne
    What types of things did the japanese people do to the Korean people during the occpation?
    (3 votes)
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  • male robot hal style avatar for user Sarfaraz
    Are S Korea and N korea in state of war till this day? If yes, then what is the present scenario? please explain.
    (5 votes)
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  • blobby green style avatar for user Isabella
    Is S Korea and N Korea get along? Do they ever get disagreements? Are they still apart of the same country?
    (5 votes)
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  • leafers ultimate style avatar for user Nick Phillipe
    Is N Korea and China still allied today? Axis of evil or something like that? And why doesn't America stop N Korea from their nuclear testing....
    (5 votes)
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    • piceratops ultimate style avatar for user Manas Pandey
      Well...they are still allies but not as great since the more liberal-ness of the PRC in the 90's. The US and UN try to "use" China in talks to get them to stop doing some things. I know for a fact that most Chinese people don't approve of DPRK due to the crazy crap they do, and it's pretty sad the the PRC and DPRK still have a pact where China has to defend N. Korea. And besides, it's not easy even for PRC to stop North Korea from gaining nukes. I mean, it's pretty hard when one's country is hell bent on becoming a military superpower with nukes.
      UPDATE: Chine recently has agreed with South Korea that the North's nuclear program is getting out of hand, and as a result, the DPRK shelled an island close the the DMZ in retaliation.
      (5 votes)
  • blobby green style avatar for user Adam Zerner
    I don't get it - what's the difference between an armistice and an end to war?
    (5 votes)
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    • spunky sam green style avatar for user History Helper
      An armistice is a temporary halt to combat, but not a complete end to a war. Thus, hostilities could be renewed shortly after. And end to a war, or peace treaty, is a complete cessation of hostilities between the two sides, and both parties would recognize each others legitimacy over their ruling territories.
      (8 votes)
  • mr pants teal style avatar for user JT Houk
    How do names work in Korea?
    (4 votes)
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    • piceratops ultimate style avatar for user Jet Simon
      Names go in this order, Last name and first name. Like how John Smith (this is the English way) , in an Asian language it would be Smith John, and some Asian languages put their last names first (such like Korean, Chinese, and etc.)
      (7 votes)
  • piceratops ultimate style avatar for user Jonathan Chin
    How many soldiers were involved in the war?
    (5 votes)
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  • hopper cool style avatar for user Micah Healy
    if the war with japan was over in 1945 why did the allies (U.S. & Russia) have to push japan out of Korea?
    (4 votes)
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Video transcript

Before we go into the actual conflict of the Korean War, let's try to get a sense of the historical environment going into the Korean War. So if you go all the way back to the late 1800s, early 1900s, the Korean peninsula-- what we now consider both North and South Korea-- they were occupied by the Japanese military. And then in 1910, the Korean peninsula is formally annexed into the Japanese empire. So the Japanese are essentially this colonial, this imperialist power here. And they stay in power in the Korean peninsula all the way until the end of World War II. And it's probably worth saying here-- and it's probably worth making and doing a bunch of videos here-- that the Japanese occupation was not a pleasant occupation for the Korean people. They subjugated the Korean people in multiple ways. Forced labor, forced prostitution. They tried to eradicate the Korean language and the Korean culture. So this was not in any way a pleasant occupation. They weren't pleasant imperialists. But you fast forward all the way to 1945, we know that Japan loses World War II. And the major two victors on the Allied side, that are kind of acting in this part of the world, are the United States and the Soviet Union. And so in 1945, you have the Soviets coming from above. That's the Soviets, coming from above. And eventually, you have the Americans coming from below. They occupy Japan first. So this is the USA. And they essentially, remember at this point, even though this is kind of the beginning of the Cold War, at this point in World War II, the United States and the Soviet Union are allies. And so United States tells us the Soviet Union, hey, why don't we just stop at the 38th parallel? The United States actually didn't even think that the Soviets would stop there, but they actually did. And from the Soviet's point of view, it's believed that they stopped there, because the United States didn't get there at the same time. So there was no one to stop them from going further South. But it's believed that the Soviets wanted to uphold their side of the agreement so that they would be a trusted party to negotiations in Europe, and maybe get more in Europe, which is what the Soviets maybe cared about more. So what happens after World War II is that the North, what is now North Korea essentially, becomes under the influence of the Soviets. Everything below the 38th parallel becomes under the influence of the United States. The Soviets essentially install this gentleman right over here to lead North Korea-- Kim Il Sung-- or the part of Korea that is north of the 38th parallel. At this point, this was just kind of viewed as a point where the Soviets and the United States should meet up. Where they would have to stop. It wasn't meant to be an actual partition of the country. But as we'll see, it actually becomes a partition of the country. But the Soviets install Kim Il Sung. He sets up a communist, essentially a communist dictatorship in the North. And this is the current leader of North Korea's dad. This is Kim Jong Il's dad. So he gets installed in the North. And in the South, if you fast forward a little bit to 1948, there's an attempt at elections. But those elections are seriously rigged. And this gentleman, Syngman Rhee, comes to power. And although he might look like a nice, pleasant man, he was actually fairly ruthless. And he is unanimously considered a strong man. And on both sides-- and so once again, this is one of those situations where you really can't call either of these guys good guys because both of them have done some pretty nasty, nasty things to each other, to soldiers on either side, and to innocent civilians. But Syngman Rhee comes to power in the south, and his, I guess, most attractive feature to the Americans is that he is not a communist. And so you have this situation setting up communist North above 38th parallel. Non-communist South, controlled by Syngman Rhee, supported by the United States. The other thing that happens is that the Soviets help build up the North Korean military. The United States is not as encouraging of a strong South Korean military. So you start having an imbalance between the military of the North and the South. And obviously, either one of these parties, Kim Il Sung wants to unite Korea under his rule, under his communist rule. Syngman Rhee wants to unite Korea under his authoritarian rule. So they're both setting up the troops along the border. And this whole time you have skirmishes going on across the border. And just to give you a context, you're probably saying, wait, Korea is right next to China. What was going on there? And if you go to China, in 1949, the Communists come to power. There was a civil war leading up to that between the Communists led by Mao Zedong, and the Nationalists led by Chiang Kai-shek. Mao Zedong comes to power. He wants to support the communists in North Korea, especially because some of those communists in North Korea actually helped fight on the communist side during the Chinese Civil War. So this is an important factor right here. Mao Zedong is interested in spreading Communism. He doesn't like the Americans in South Korea, and he feels some type of allegiance to the communists in North Korea. So now you fast forward to June 25, 1950. And in the North, you have a major event. The North Korean army-- and it's not called North Korea at this point-- they both consider themselves Korea, competing, I guess, governments of Korea. The army in the North is disproportionately stronger than the South, and so they invade. They view this as their chance at unifying the peninsula. And essentially, they're able to almost just storm through the Korean peninsula. Immediately, when that happens, the UN, and especially the United States-- and this is because at this point, the Soviet Union was boycotting the Security Council, so they couldn't even veto it-- the UN immediately starts supplying naval and air support for the South Koreans. But the disparity is so big that the North Koreans are able to just keep marching forward. Within a few days, literally by July 1, the United States decides to commit ground forces, because we had substantial ground forces in Japan, which isn't that far away. Just to give you a global perspective, this is the Korean peninsula right here. And this is Japan. I know I could have probably found a bigger picture of that. But America had military forces in Japan that they could send, and so the Americans enter the battle in a major way, very early on. But that doesn't stop the North Koreans for some time. So the North Koreans get all the way, they're able to occupy all of the Korean peninsula, except for the northeastern corner. So they get around this far. Over here, you have the city of Pusan. And this is called the Pusan Perimeter. And it's at the Pusan Perimeter that you have a little bit of a, the United States and Korean forces combined are able to halt the North Koreans. And you have a slight stalemate for a couple of months here. But while that stalemate is happening, the United States is able to-- and especially the UN, but it's mainly the United States-- is able to build up significant troops within the Pusan Perimeter. But even more, and at this point, the United States and the UN forces, go under the control of Douglas MacArthur, General Douglas MacArthur, who's a bit of an interesting character. Until this point, he was able to rule Japan with an iron fist. He's a hugely popular war hero in America, and the current president, Truman, kind of has a little trouble controlling MacArthur, especially during the Korean War. And we'll see that MacArthur really oversteps his bounds during the course of this war. Now, at this point, you have the South Koreans and the Americans kind of cornered down here inside of the Pusan Perimeter. It looks like North Korea's on the verge of victory. But the US is able to build forces. And the Korean War really just starts becoming into a game of Risk. I don't know if you've ever played the game of Risk, but whenever it's somebody's turn, they're able to spread their forces. But then they get spread thin, and then the other side's able to come back. And what we'll see is the rest of the Korean War is essentially a back and forth between the Communists in the North-- supported by the Chinese, although the Chinese aren't in the war officially just yet-- and then the Americans in the South. And the first really smart thing that MacArthur does is he says, look, instead of trying to fight our way through the Korean forces that are over here, why don't we just kind of outflank them? And why don't we use our navy to do an amphibious landing of an army at Incheon? So on September 15, while you have the stalemate over here, the United States, they have an amphibious landing. So they send troops from all of these places. They have an amphibious landing at Incheon, which is near Seoul. So they land right over, they land at Incheon, which is roughly over there. I'm not super accurate here. And what's interesting about that is, in any battle, all of these Korean troops right here, they have supply chains. They have to get food and supplies and fresh troops from up here. And so the further in you go into enemy territory, the more spread out your troops get. And the strategy here is instead of fighting through this, what if we outflank them and are able to land a significant force right here, and immediately disrupt the supply lines of the North Koreans. And that's essentially what the Americans did. And it was successful. So MacArthur looks like a genius over here, and he's able to retake Seoul. He's able to take what's kind of the North Korean capital at this point, Pyongyang, and you have the Americans marching north. So all of a sudden, it started off with the North Koreans being able to roll down, and now all of a sudden the Americans and the South Koreans are able to roll up. And they're feeling pretty good about themselves. And the whole time, Truman's trying to keep MacArthur under check. MacArthur is excited. He's ultra confident. He thinks that the troops are going to be home by Christmas. He doesn't think China is serious about supporting the North Koreans, and even more, he almost, it seems, like wants to pick a fight with China because he wants to maybe eliminate communism in China as well. He viewed it as he's on this mission to eliminate communism from all of Asia. So Truman is saying limited war. Don't cross the Yalu River, and be careful. Don't start attacking Chinese up here and enrage them, and you're going to have them enter the war. MacArthur doesn't take that too seriously. And he also says, look, I have to start bombing bombs across the Yalu River so that the Chinese won't be able to send troops and supplies to aid the North Koreans. So he's marching up, all confident, going up against the Yalu River. And this whole time, the Chinese, under Mao Zedong, are sending a pretty substantial army. And they're able to do it secretly. They're able to march at night, and they even have these policies where if any surveillance planes go overhead, all of the Chinese soldiers have to freeze. And if they don't freeze, someone else is allowed to shoot them. So everyone wants to freeze so that no one can really see them from above. So it's this really secret buildup of troops across the Yalu River, and this whole time MacArthur is just ultra, ultra confident about what's happening over here. But then you fast forward until the end of October, the Americans think that they're on the verge of winning the Korean War. And all of a sudden, you have the Chinese cross the Yalu River. And the Americans didn't even know that the Chinese had major forces ready to cross. And once again, it's just like a game of Risk. Now you have the Chinese cross. They catch the Americans unsuspected. They engage a few times. The Americans weren't sure if the Chinese were serious. So they keep re-engaging them, but it becomes clear, yes the Chinese are serious. And essentially the Chinese are able to push back the Americans and the South Koreans all the way back so that they are able to recapture Seoul. But once again, like any game of Risk, now the Chinese are spread thin. The Americans and the South Koreans, and all the other UN forces-- although the UN forces are mainly the Americans-- are able to regroup. And then, in March-- so Seoul has changed hands four times-- so in March, they're able to retake Seoul again. And at this point, MacArthur is ultra confident. He's telling the Chinese, you've essentially lost. He's even trying to get permissions to use nuclear weapons against the Chinese. To some degree, he doesn't even think he needs the permission of Truman to stop. It sounds like he's eager to push the Chinese further back, even though they surprised him the first go around. So Truman has enough of this wild card guy, who thinks that he can call the shots and use nuclear weapons if he wants to, willy nilly. And so Truman finally dismisses MacArthur in April of 1951. And at this point, you start having a stalemate near the 38th parallel. So that you start having a stalemate across this border right over there. And both sides think the end of the war is imminent. They're like, OK, we're back to where we both began. We should both stop here. But the negotiations, unfortunately, took over two years. And there was a lot of back and forth about what to do with prisoners of war and all of the rest. But it finally took two years so that on July 27, 1953, you have an armistice signed between the two parties. And I want to make it clear, an armistice agreement, it is not a peace treaty. It is not saying that we both agree that this is the border of our two new countries and that we are now at peace with each other. All an armistice means is that we're going to stop fighting. It is not a formal end to the war. So in theory, North and South Korea, even to this day, are in a state of war. And to this day, I'm recording this video in 2011. Maybe if you view this in the future, hopefully they won't be in an official state of war. But they're in an official state of war under an armistice. They've just agreed to stop fighting. So all in all, you have this hugely bloody battle with all of these atrocities going on on both sides. Syngman Rhee when he was, the first time when the North Korean troops were rolling in to South Korea, he essentially, beforehand, he was imprisoning a bunch of people who he suspected to be communists. We're not talking about people, I'm talking about whole families sometimes. And when he was retreating, he essentially allowed the massacre of a huge number of people who were just suspected of being communists. These weren't just military men. These were women. These were children. These were entire families, so he is guilty of that. And Kim Il Sung just as guilty when the North Korean soldiers infiltrated South Korea in Seoul, they committed atrocities killing civil servants, killing any of the established intellectuals in the area. So on both sides. This hugely horrific war. And just to get a sense of what was happening. Korea isn't a huge country, but you have within Korea, the civilian deaths, 1.5 to 3 million civilian deaths and the consensus is at 2 million. And this tells you how ugly war is that you can't even estimate how many people died to the nearest 500,000 people. You just don't know what happened. Two million people died in a country that's not too big. All in all, you have about 40,000 American soldiers dying. China loses on the order of, depending on the estimates, 400,000 soldiers. I mean the estimates are all over the place. North Korea loses, on the order, same magnitude of soldiers. South Korea loses several hundred thousand soldiers. So you have this hugely bloody battle, this hugely bloody war, I should say, that really ends with an outcome that wasn't so different from where it started.