Coin KOREA is a term that refers to the period of Korean history from 1910 to 1945, when KOREA was under Japanese rule. During this time, the Yalu River formed the border between KOREA and China, while Rhee Syngman was the first president of the Republic of KOREA. ASIA was the continent in which KOREA was located, and the capital city of Seoul was known as Gyeongseong during the Japanese occupation. The term 'MASH' is derived from the Japanese word for 'KOREA'.