Sejong the Great
Before the creation of Hangul, people in Korea (known as Joseon at the time) primarily wrote using Classical Chinese alongside phonetic writing systems based on Chinese script that predated 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 that needed to be learned, there was much difficulty in learning how to write using Chinese characters for the lower classes, who often lacked the privilege of education. To assuage this problem, King Sejong created the unique alphabet known as Hangul to promote literacy among the common people. His intention was to establish a cultural identity for Korea through its unique script.
History of the Joseon dynasty
During the rule of Sejong, Korea saw technological advances in natural science, agriculture, literature, and traditional medicine. Because of his success, Sejong received the title "King Sejong the Great of Joseon". His most remembered contribution is the creation of Hangul, the Korean alphabet, in 1443. Before that, Korean literati had used the Hanja writing system—traditional Chinese characters with Korean pronunciation and meaning—and a written language known as Hanmun, which was basically Classical Chinese, for official court documents. Everyday written use of Hanja and Hanmun ended gradually in the latter half of the 20th century.