Liberation and Division — The Day the 38th Parallel Was Drawn
In August 1945, Japan's defeat brought liberation to the Korean Peninsula. Yet behind the jubilation, two great powers — the United States and the Soviet Union — drew a single line across the map. The 38th parallel. Why was the peninsula split into north and south? This episode traces, on a neutral and factual basis, how two governments came to be.
June 12, 2026
In the previous episode, we saw the thirty-six years of colonial rule under the Government-General of Korea. The cries of the March First Independence Movement, the clashing assessments of modernization and exploitation, and the mobilization of wartime. The peninsula lived through an age with no end in sight, as part of the territory of the Japanese empire.
But that age ended suddenly.
On August 15, 1945, Japan accepted the Potsdam Declaration and surrendered unconditionally. For people under colonial rule, it was the day of liberation. On street corners, flags that had until then been forbidden are said to have fluttered, and cries of joy rang out. After thirty-six years, the peninsula was supposed to be able to choose its future with its own hands.
Yet before the jubilation of liberation had even cooled, a single line that no one had wished for was drawn across the map of the peninsula. The 38th parallel. This line would go on to determine the peninsula’s fate.
A Line Drawn in Thirty Minutes
Why was the peninsula divided? The circumstances are often spoken of as an irony of history.
On August 8, 1945, the Soviet Union abrogated the Soviet-Japanese Neutrality Pact, declared war on Japan, and began its invasion of Manchuria and the northern part of the Korean Peninsula. The Soviet advance was swift, and the U.S. government grew anxious that, left unchecked, the Soviets might occupy the entire peninsula. And so, under the pretext of dividing between the two powers the area in which Japanese forces would surrender, it sought to decide hastily on a boundary line between the two armies.
According to the Japanese edition of National Geographic and other sources, the men who handled the practical work at the time, in the U.S. State-War-Navy Coordinating Committee, were two young colonels, Dean Rusk and Charles Bonesteel. Standing before a wall map in a magazine, they are said to have chosen, in roughly thirty minutes, the 38th parallel as a draft boundary that divided the peninsula into north and south more or less in half. That the capital, Seoul, could be included on the southern side, and that the peninsula could roughly be split into two equal halves, are said to be the reasons this line was chosen.
This proposal was presented to the Soviet Union, which agreed to it on August 16. On August 17, General Order No. 1 of the Allied forces stipulated that Japanese forces north of the 38th parallel would surrender to the Soviet army, and those to the south to the American army. Thus the Soviet army moved into the north and the American army into the south, and the peninsula was divided into two occupation zones. The Soviet army entered Pyongyang in late August, and the American army landed at Incheon in early September, each establishing military government in its occupation zone.
What is striking is that the people of the peninsula had no involvement whatsoever in the drawing of this line. Without waiting for the voices of those directly concerned, who had only just met liberation after thirty-six years of colonial rule, the line was drawn for the convenience of great powers. This was also an event that once again threw into relief the fate of a peninsula that had long been caught between the great powers of Qing China, Japan, Russia, the United States, and China. Not who drew the line, but who did not draw it — that question quietly points to the essence of the division.
A line of just a few centimeters on a map would come to divide the peninsula’s destiny. This was an event that symbolized the very theme of this series — a peninsula tossed about within the dynamics of great powers.
The Conflict Over Trusteeship
Attempts to keep the division a temporary thing did, in fact, exist.
In December 1945, a conference of the foreign ministers of the United States, Britain, and the Soviet Union was held in Moscow, where the future of Korea was discussed. What was agreed there was a plan to establish a provisional government in Korea and then to carry out a trusteeship by the four nations — the United States, Britain, China, and the Soviet Union — for up to five years. Rather than granting full independence at once, the idea was to spend a fixed period preparing for self-reliance under the guardianship of great powers.
But this trusteeship plan provoked fierce conflict between supporters and opponents among the people of the peninsula. For many, after the liberation they had finally won following thirty-six years of colonial rule, to come under foreign guardianship again was hard to accept. While movements of opposition arose across the land, forces that shifted their stance toward support also emerged, and the confrontation between left and right deepened further.
- August 1945
Japan surrenders. The United States and the Soviet Union divide and occupy the peninsula along the 38th parallel.
- December 1945
At the Moscow Conference of the three foreign ministers, a trusteeship plan of up to five years is agreed upon.
- 1947
The U.S.-Soviet Joint Commission breaks down. The Korean question is brought before the United Nations.
- August 1948
The Republic of Korea is established in the south.
- September 1948
The Democratic People's Republic of Korea is established in the north. Two governments stand side by side.
Behind this lay the internal circumstances of the peninsula after liberation. In the north, the building of a socialist-style system advanced under Soviet backing, while in the south, forces that carried on the existing order held power under American military government. The differences in the systems of the occupying great powers came directly to define the shape of each society, north and south. Though they were the same Korean people, the image of the nation they aimed for grew further apart, day by day, between north and south.
The U.S.-Soviet Joint Commission, set up to mediate this conflict, also lacked any approach toward compromise amid the intensifying Cold War, and broke down in 1947. To the question of how to form a unified government for the peninsula, the United States and the Soviet Union could not produce a common answer. The problem was carried over to the United Nations.
Two Governments Are Born
The United Nations sought to create a unified government through a general election across the entire Korean Peninsula. But the Soviet Union and the authorities in the north refused this and did not permit the election observation team to enter the north. As a result, the election came to be held only south of the 38th parallel.
On August 15, 1948, the founding of the Republic of Korea was proclaimed in the south, and Syngman Rhee became its first president. Then, on September 9, the establishment of the Democratic People’s Republic of Korea was proclaimed in the north, and Kim Il-sung took office as premier. Thus, within a single people, two governments came to stand side by side, each claiming to be the legitimate one.
The division did not stop at the boundary between north and south. In the south as well, movements opposing the establishment of a separate government erupted in various places, and on Jeju Island and elsewhere, turmoil accompanied by many victims is said to have occurred. Regarding these events, assessment and investigation continue even now over their background and the scale of the victims, and the figures are subject to differing accounts. For the people of the peninsula, the division was at once a decision of distant great powers and a reality that tore their own society apart.
Just three years from liberation. The freedom that should have been met in jubilation had taken on the form of division, of two states. And this division did not stay a line on the map.
The 38th parallel, a line that had originally been drawn as a mere expedient. In the next chapter, it would blaze up as the front line of a war that drew the world into its flames.
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