Korean has a rich and fascinating language history that spans nearly two millennia across multiple writing systems! Here, we’ll give you a brief overview of Korean language history and how Korean has gone from being written with hanja (Chinese characters) to Hangul, the writing system native and unique to Korea.

Korean language history is divided into three main periods:

We’ll start our journey with Old Korean and explore how it was first written!

What was originally spoken on the Korean peninsula?

Most scholars think that by 600 CE (when the Old Korean period started), what we today call Korean was already the dominant language of the Korean peninsula and perhaps the only language spoken there.

But there are signs that Korea had much more linguistic diversity before this period. Two early Chinese histories from this era, Wei Shu ("The Book of Wei") and Hou Han Shu ("The Book of Latter Han"), give indications that some parts of Korea had Japanese-like names and were inhabited by Japanese-like groups several centuries before the Old Korean period. There is also evidence from Korean history records of multiple languages co-existing in Korea.

Much of what we know about prehistoric Korea comes from a book called Samguk Sagi ("Record of the Three Kingdoms"). Interestingly, this text shows that different words were used throughout the Korean peninsula:

  • The character 勿, pronounced something like "mur," was used to stand for the word "water" in southeast and southwest Korea. This word sounds like it could be the predecessor to the modern Korean word 물 (mul, "water").
  • The characters 買 and 米, pronounced like "may," were used to stand for the word "water" in central Korea. This word sounds like the ancient Japanese word for "water"!

It seems likely that at some point in early Korea, the peninsula was home to multiple language groups, including some people who spoke an ancestor of the Japanese language!

Old Korean

The period between the 600s to the 900s is known as Old Korean, the earliest documented period of the Korean language. This stage of the language was not written in the Korean alphabet Hangul—it hadn’t been invented yet!—but was instead written with Chinese characters, which are called hanja in Korean (한자 or 漢字 hanja literally means "Chinese characters").As you might guess, Chinese characters are well-suited to write Chinese, but they can’t immediately be adapted to write other languages because they are so closely associated with particular meanings in Chinese. This became a problem for Old Korean scribes. Most Old Korean texts are really just written in Classical Chinese, but Korean scribes also wanted to write words in their own language.

To get around this problem, ancient Korean scribes started using Chinese characters in two ways: sometimes with their original Chinese meaning, and sometimes to just mean the sound of the Chinese word, to sound out a Korean word. This makes Old Korean really challenging for scholars to read today, because it's not immediately clear if the character is meant to be Chinese or Korean! The scribes who wrote Old Korean spent years of study to master Chinese, which meant that literacy was limited mostly to elites, Buddhist priests, and government officials. For the modern reader, reading these old texts requires years of study in Classical Chinese, Classical Korean, and linguistic methods in order to begin decoding texts. Despite decades of research, what we "know" about Old Korean is still not much more than educated guesses! Curious to know more about the differences? Write to Dear Duolingo!

The impact of Chinese on Korean

Because Chinese characters were so important for reading and writing in ancient Korean, Chinese influenced Korean in other ways too, including through a large number of borrowings. These words are generally thought to have entered into Korean during the 7th to 13th centuries CE, a time when China exerted a great deal of cultural and literary influence on all of its neighbors, not just Korea but also Japan and Vietnam. Somewhere between 50% to 70% of Korean vocabulary today is constructed out of borrowed Chinese words, and a very significant proportion of everyday words in Korean come from Chinese. These words were borrowed over 1000 years ago, and sound changes in both Korean and Chinese languages mean that they usually don’t sound very similar to spoken Chinese today:

Mandarin Chinese Korean Japanese
"future" wei-lai mi-rae mi-rai
"connection" guan-xi kwan-gye kankei

Learning Korean is especially cool if you have studied another East Asian language like Japanese or Chinese, because you can start to unpack the ancient connections between words these languages borrowed from each other. Eventually, you’ll even be able to predict what a Korean word should sound like, based purely on your knowledge of a Chinese or Japanese word!

Middle Korean and Hangul

Middle Korean is generally thought to span almost 700 years from the mid-900s (when the Korean peninsula became fully unified by the Koryŏ Kingdom) to around 1600 (when the Japanese invaded Korea). The first 500 years of this period (900s to 1443) are referred to as Early Middle Korean, and this language was written like Old Korean, using Chinese characters either to represent whole words or to sound out a Korean word.

However, this changed dramatically starting in 1443. In that year, King Sejong of the Chosŏn Dynasty (often called “Great King Sejong”) commissioned the creation of an alphabet called Hangul, and in 1446 it was presented to the Korean people in a series of books, the most famous being 훈민정음 (Hunminjŏngŭm, “The Correct Sounds for Instructing the People”). The story goes that King Sejong was troubled by the lack of literacy among the common people, and was moved to create a simpler writing system that anyone could learn without extensive education in Chinese. After the invention of Hangul, we have essentially perfect knowledge of both the sound system and pronunciation of Korean! The creation of a native writing system was a defining moment in Korean history, and it is still celebrated every year on October 9th.

These Middle Korean texts give us a lot of information about the language's grammar and sounds, and an educated speaker can probably understand a fair amount of Middle Korean if they read diligently, especially if they use a dictionary. If you have learned Hangul, you may be surprised to see that there were some additional letters in Hangul when the alphabet was first invented. These were:

  1. a vowel ᆞ that was probably pronounced like "uh" as in English cut
  2. a consonant ᄫ that was pronounced like the Spanish v / b
  3. a consonant ᅀ that was pronounced like English z
    There were a few more letters that differ from modern Hangul in use at this time, but they are either rare or only used to write foreign words.

The Middle Korean period ended at around 1600. The stability of Korean society during this time was shattered by the Japanese invasions of Korea between 1592 and 1598, which brought untold destruction to the peninsula. Decades later, when Korean society finally recovered and people began to write literature once again, many spellings and conventions were adapted to reflect changes in how people now spoke.

Modern Korean

Modern Korean is generally thought to have begun in the early 17th century and continues to the present. Educated speakers of Korean today won’t have much trouble reading Hangul texts from the 1700s onwards, though the style and vocabulary may sometimes sound archaic. Although Chinese characters continue to have some limited use in the modern language—especially in academic, historical, and religious contexts—Modern Korean is characterized by the almost exclusive use of Hangul in writing, especially since the end of World War II and the liberation of Korea from Japanese occupation.

Even though Koreans no longer use Chinese characters in writing, the language is still full of words borrowed from Chinese. But Modern Korean also has a growing number of words borrowed from English, too, many of them for modern objects like computers (컴퓨터 k’ŏmp’yut’ŏ) and television (텔레비전 t’ellebijŏn). Some Korean words are fusions of a Korean word and an English word, like 소개팅 sogaet’ing meaning "blind dating" (a combo of sogae "introduction" and English meeting).

Occasionally, European words were borrowed into Japanese and then later made their way into Korean, and each change along the way sometimes resulted in strange words that most Koreans don’t know are borrowings at all! Here's an example of how those multiple borrowings ended up creating uniquely Korean words:

  1. Japanese borrows a German word. For example, the German word Deutsch (which means "German") was borrowed into Japanese to mean "Germany."
  2. Japanese makes the word its own. The new Japanese word for "Germany" was pronounced doitsu, sort of the Japanese version of the sounds in Deutsch, and it was written with two Chinese characters to sound out do (独) and itsu (逸). That works for sounding out doitsu, but the meanings of those characters are actually "lone" and "great"!
  3. Korean borrows the new Japanese word. Korean borrowed the Japanese word for "Germany," but the two characters were read with their Korean pronunciations: tok and il. This created the new Korean word 독일 togil for "Germany"—which no longer sounds anything like Deutsch!

As Korean culture becomes ever more popular across the globe, the Korean language continues to change in the 21st century, with new words coming into the language and being innovated. I hope you’ve enjoyed learning a little bit about the history of the Korean language and how it has been written through time!