Hangul Day in South Korea

Hunmin Jeongeum (Hangul Day, also known as Hangul Proclamation Day or Korean Alphabet Day) is a national holiday in Korea commemorating the invention and proclamation by King Sejong the Great of the Hangul repertoire, the alphabet of the Korean language. It is celebrated on October 9 in South Korea and January 15 in North Korea.

The discovery in 1941 of an original copy of the Hunminjeongeum Haerye, a volume of commentaries to the Hunmin Jeongeum, appeared shortly after the document it commented on, revealing that the Hunmin Jeongeum was announced during the first ten days (sangsun; 상순; 上旬) of the ninth month. The tenth day of the ninth month of 1446 is equivalent in the lunar calendar to October 9, 1446 in the Julian calendar. After the South Korean government was established in 1945, Hangul Day was declared a working holiday every October 9.