The Great King Sejong, who reigned from 1418 to 1450, was the fourth king of the Joseon Dynasty in Korea. He is best known for creating the Korean alphabet, known as Hangul, which made literacy accessible to the common people. His reign is often regarded as a golden age of culture and science in Korea. In addition to his linguistic achievements, King Sejong promoted advancements in various fields, including agriculture, astronomy, and military technology. He established the Hall of Worthies, a group of scholars who contributed to the development of new inventions and policies, further enhancing the prosperity of the nation.