As the Second World War had ended with surrender of Japan, Korean peninsular met liberation, as agreed by allied force at the time of the war. Korean peninsula were divided by the 38 boundary line, the north of the boundary line were stationed by the soviet army were and the south of the boundary line were stationed by American army forming 38 line as the military boundary line. The end of 19th Century, the world powerful countries developed power competition to make Korean peninsula under their dominant. In East Asia region, the Japan joined that world power rank of imperialism by succeeding in enhancing the wealth and military strength of a country in1967. Japan ended the Sino-Japenese war in 1984 and the Russo-Japanese war in 1904 with victory over Korean Peninsula in the middle and forced to unite the Korea with Japan under the tactic approval of American and Soviet union. Our nation tried hard to achieve the independency in union such as 3.1 independent Act. And establishment of an interim government of Korea but failed to win the independency of the country by our own accord. Eventually, we met the independence with the agreement of the allies at the time of the war with Japan, as Japan had defeated against allies and surrendered unconditionally. America, the country which was leading the World War 2, had already planned for the policy about the management of postwar problems during the war period, announced the Atlantic Charter presenting the basic principles for the world peace in future with an agreement of Churchill, the prime minister of U.K. in Aug. 1941. In the Atlantic Charter, it was made clear that all non-aggressor nations have the national self-determination regardless of the geographical location. Based on such principle, the war situation started turning in favor of Allies in 1943, and since than, the allied nations started to discuss about setting up of the security organization for the postwar world peace. From this time, allied nations, especially America was attentive to postwar problems of the colonies of Japan in Asia. During this process, the independency problem of Korea was explored in the international politics. The main conferences related to the Korea's independency for the postwar management plans are the Cairo Conference by America, U.K and China in Nov.1993, the Yalta Conference in Feb. 1945 and the Potsdam Conference in June 1945.

After the Potsdam Conference, America dropped the atomic bomb in Hiroshima, Japan on 6th Aug. 1945. U.S.S.R declared war toward Japan on 8th Aug 1945 and next day stated to attach toward Manchuria and Korea peninsula. And at the same day, U.S.A. dropped 2nd atomic bomb in Nagasaki Japan. On 15th Aug. 1945 Japan announced unconditional surrender as the result of the USSR's participation of the war and the twice airdrop of atomic bomb by American. On 2nd Sep. the day, Japan had signed the unconditional surrender instrument, the General MacArthur, the supreme commander of pacific area allied force, made official announcement of the 1st general order The order is to enforce the surrender of Japan and demilitarize in Korea Peninsula, but also containing the contents about U.S.S.R taking the charge of northern part of Korea from 38line and America taking the charge of south of Korea from 38line as a boundary. Like this, 38line was the military demarcation line between the U.S.S.R. set up as a tentative measure to demilitarize accepting the surrender by Japan who were stationed in Korea at that time.