Koreans believe the myth as history. Even the president of South Korea says “Our 5,000 years of history”… oh boy.
The thing is… you can’t include myths as part of your “history”.
History of a nation starts when clear evidence of a political hierarchy and state (including proto-state) structure have emerged in the society, the society must also have attained a sufficient level of development, for example, with the elites being actually able to record history through writing, to be really considered as a civilization. This thus excludes all primitive/tribal societies of hunter and gatherers or nomads.
Right.
It’s Koreans who are distorting history. I’m beginning to think that Korea eliminated the use of Chinese character so that nobody reads real historical documents to verify what they had been taught.
One of the oldest Korean flag: titled “Korea belongs to Great Sino” or “Korea is vassal kingdom of China” (大清国属 高麗国旗) in Chinese characters.
Korea officially used Hanja(Chinese character) until she gained her independence from Sino in 1895. Today, ordinary Koreans cannot reads any official documents prior to 1895.
This is one of the reasons why most Korean kids(or even grown-ups) do not know what the “Independence gate” in Seoul stands for.
I have actually read Korean school textbook. And there was no explanation of the article 1 in the treaty of Shimonoseki at all.
So, I figured, I should ask Koreans how they think. I asked the following 3 questions. This was 2 years ago.
1. Do you think Japanese school textbook distorts history?
2. Have ever read one? Or do you know what the Japanese textbook say?
3. Do you know why “Independence gate” was built?
Their answers scared hell out of me.
Everybody I asked said “yes” to the question #1 and “no” to the question #2. They were blaming Japan for whatever reasons they even don’t know.
Finally, in response to the question #3, some had no clue what the Independence Gate stands for. Some(after searching the web) said “It represents our intention to keep our independence forever. Especially, from Japan!”. Some replied “Because we beat Japan and gained independence from Japan. ”
Oh boy…
Another observation was that every time I talked to North Koreans about politics or history, the first thing they tend to mention was
“Our great leader Kim Jong-il… yada yada yada”
Every time a Japanese talked to South Koreans about culture or history, the first thing they tend to mention was
“Korean history is 5000 years old. We taught you japs all the culture… yada yada yada”
South Koreans and North Koreans are pretty much the same.
It is sad if I offend somebody with my comment, but this is based on my first-hand experiences and observations.
[Recommend reading]
A Japanese on Korea 
How old were the kids that you surveyed. Age Range?
I did not do any “survey”. I just asked a few Koreans online. I’m not that brave. 😉 They would kill me if I said “Korea was a vassal state of China” or “5000 year-old” is a myth. They are believing in the myth.
On your first statement, that Gojoseon is not the first country to be founded by Korea;s ancestors:
Gojoseon was founded in 2333BC, which can be seen through , which was written by the monk Ilyeon.
These are artifacts that show that Gojoseon, such as Guindol, Sehyeong-dong sword, and plain pottery, excavated from the Korean Peninsula, was active on the Korean Peninsula.
In Lee Seung-hyu’s “The King Ungi,” Dangun Joseon was recorded as the first country in our satisfaction.
On your second statement, that 大清国属 高麗国旗 proves that Korea was a vassal state of China:
An article named, “태극기에 관한 잘못된 정보” states, “What it means is that Taegeukgi was originally a national flag ordered by the Qing Dynasty, and the original name was the Korean flag of the Qing Dynasty. To translate the meaning, the flag of Korea, a subordinate country of the Qing Dynasty, is the original name, and it is widely claimed that Joseon is a subordinate state of the Qing Dynasty. And as a basis for that, there is a picture in Lee Hong-Jang’s 1886 Qing Dynasty’s treaties made by foreign countries, classified by type, and recorded in the book of Trade and Trade, Seong-Anhui, 通商章程成案彙編. However, this is just crap that Hong-Jang Lee came up with. It turned out that in a book called Flags of Maritime Nations of the US Navy’s maritime nations, which Hong-jang Lee made four years before the creation of that book, it was revealed that the Korean flag had already been written in the name of the Korean national flag COREA Ensign.”
Also, the article “Was Korea Ever Part of China? It’s Complicated,” it says, “Chinese history covers a very long period and a great diversity of phenomena. During some phases of Chinese history, the geographical entity that is now the modern state was ruled by dynasties that were neither principally nor originally speakers of the Chinese language. These dynasties notably included the Yuan (or Mongol: 1271-1368) and the Qing (or Manchu: 1644-1912). Chinese scholars generally refer to these dynasties as ‘Chinese’ in the sense that China has been (some claim still is) a multi-ethnic state.
During these dynastic periods, Korea was certainly invaded and occupied by the armies of these states. Korea then became as much a part of their realms as many other peripheral regions ruled by local notables. So the claim that Korea was not part of China would have to exclude these eras. However, the rulers of the Ming dynasty (1368-1644) routinely awarded the Korean king his official title, indicating his dependent or tributary relationship—which explains why the Ming took such trouble, despite other pressing problems, to send armies in the 1590s with the mission to expel Japanese invaders of the Korean peninsula. This latter set of exchanges might, nevertheless, be set aside as not strictly constituting possession or domination.”
In conclusion, Korea was in fact a vassal state of China when Mongol invaded Korea, and King Injo (인조) surrendered. However, Goryeo’s struggled for freedom during the time of King Kongmin (공민왕), and did many things to loosen the Chinese’s grip on Goryeo. Korea got their true freedom during the treaty of Shimonoseki.