Hangeul, Korea’s official language, was first invented by King Sejong during the mid-15th century. Originally called Hunminjeongeum, the language was fully conceived in 1443, and further promulgated by King Sejong of the Joseon Dynasty in 1446. At the time of its inception, the language consisted of 17 consonants and 11 vowels. Currently, 3 of the originally established consonants and 1 vowel are no longer in use, bringing the total number of characters to 24. Korea’s Hangeul vocabulary is formed by the selective combination of vowels and consonants to create words.

The official name for the Korean language was changed to 'Hangeul' in 1910. Hunminjeongeum Proclamation Day was called ‘Gagya Proclamation Day’ up until 1926, and it wasn’t until 1928 that it was changed to its current celebration, ‘Hangeul Proclamation Day’.