The National Flag of South Korea is known as Taegukki, the meaning of which has originated from the old oriental philosophy called the theory of Um-Yang, pronounced as Yin-Yang in Chinese. The need for a national flag was felt by the Koreas while it was preparing to wrap up the Korean-American Treaty of Commerce, during the reign of King Gojong of the Joseon Kingdom. Following the establishment Republic of Korea in 1948, the present South Korean flag was adopted on January 25, 1950. The National flag of South Korea was designed by Bak Yeong-hyo, in 1882. Bak Yeong-hyo was Korean ambassador to Japan during the reign of King Gojong. On 6 March, 1883 King Gojong proclaimed the Taegeukki the official National flag of Korea.