Hangul Day

Hangeul Day (한글날)
Hunmin Jeongeum Eonhae
Official name	Hangeul Day (한글날) Chosun-gul Day (조선글날)
Also called	Hangeul Proclamation Day Korean Alphabet Day
Observed by	North Koreans and South Koreans
Type	National, Cultural
Significance	Commemorates the invention of hangeul
Date	October 9 (South Korea) January 15 (North Korea)
Frequency	annual

Hangeul Day
South Korean name
Hangul	한글날
Revised Romanization	Hangeullal
McCune–Reischauer	Han'gŭllal

Chosŏn'gŭl Day
North Korean name
Chosŏn'gŭl	조선글날
Revised Romanization	Joseongeullal
McCune–Reischauer	Chosŏn'gŭllal

The Korean Alphabet Day, known as Hangeul Day (한글날) in South Korea, and Chosŏn'gŭl Day in North Korea, is a national Korean commemorative day marking the invention and the proclamation of Hangul (한글; 조선글), the alphabet of the Korean language, by the 15th-century Korean monarch Sejong the Great. It is observed on October 9 in South Korea and on January 15 in North Korea. In 2013, Hangul Day became a national holiday in South Korea.

In South Korea, the holiday is known as Hangeul Proclamation Day, or Hangeul Day for short, and is celebrated on October 9.

In North Korea, the holiday is called Chosŏn'gŭl Day and is celebrated on January 15 to mark the date, January 15, 1444 (1443 in lunar calendar).

Before the creation of Hangul, people in Korea (known as Joseon at the time) primarily wrote using Classical Chinese alongside native phonetic writing systems that predate Hangul by hundreds of years, including idu, hyangchal, gugyeol, and gakpil. However, due to the fundamental differences between the Korean and Chinese languages, and the large number of characters needed to be learned, there was much difficulty in learning how to write using Chinese characters for the lower classes, who often didn't have the privilege of education. To assuage this problem, King Sejong created the unique alphabet known as Hangul to promote literacy among the common people.

According to the Sejong Sillok (세종실록; 世宗實綠), King Sejong proclaimed publication of Hunmin Jeongeum (훈민정음; 訓民正音), the document introducing the newly created alphabet which was also originally called by the same name, in the ninth month of the lunar calendar in 1446. In 1926, the Korean Language Society, whose goal was to preserve the Korean language during a time of rapid forced Japanization, celebrated the octo-sexagesimal (480th) anniversary of the declaration of hangeul on the last day of the ninth month of the lunar calendar, which is on November 4 of the Gregorian calendar. Members of the Society declared it the first observance of "Gagyanal" (가갸날). The name came from "Gagyageul" (가갸글), an early colloquial name for hangeul, based on a mnemonic recitation beginning "gagya geogyeo" (가갸거겨). The name of the commemorative day was changed to "Hangullal" in 1928, soon after the term "hangul", coined originally in 1913 by Ju Si-gyeong, became widely accepted as the new name for the alphabet. The day was then celebrated according to the lunar calendar.

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Wikipedia