United Nations Command


United Nations Command is the multinational military force established to support the Republic of Korea during and after the Korean War. It was the first attempt at collective security by the United Nations after the Charter of the United Nations was signed.
The UNC was established on 24 July 1950 following the United Nations Security Council's recognition, on 7 July, of North Korean aggression against South Korea. The motion passed because the Soviet Union, a close ally of North Korea and a member of the UN Security Council, was boycotting the UN at the time over its recognition of the Republic of China rather than the People's Republic of China as 'China'. UN member states were called to provide assistance in repelling the North's invasion, with the UNC providing a cohesive command structure under which the disparate forces would operate. During the course of the war, 22 nations contributed military or medical personnel to UN Command; although the United States led the UNC and provided the bulk of its troops and funding, all participants formally fought under the auspices of the UN, with the operation classified as a "UN-led police action".
On 27 July 1953, United Nations Command, the Korean People's Army, and the Chinese People's Volunteers signed the Korean Armistice Agreement, ending open hostilities. The agreement established the Military Armistice Commission, consisting of representatives of the signatories, to supervise the implementation of the armistice terms, and the Neutral Nations Supervisory Commission, composed of nations that did not participate in the conflict, to monitor the armistice's restrictions on the parties' reinforcing or rearming themselves. In 1975, the UN General Assembly adopted resolution 3390, which called upon the parties to the Armistice Agreement to replace it with a peace agreement, and expressed the hope that UNC would be dissolved on 1 January 1976; however, as of 2025, the UNC continues to maintain and enforce the Armistice Agreement.
Since 1953, UNC's primary duties have been to maintain the armistice and facilitate diplomacy between North and South Korea. Although "MAC" meetings have not occurred since 1994, UN Command representatives routinely engage members of the Korean People's Army in formal and informal meetings. The most recent formal negotiations on the terms of Armistice occurred between October and November 2018. Duty officers from both sides of the Joint Security Area conduct daily communications checks and have the ability to engage face-to-face when the situation demands.

Origin and legal status

United Nations Command operates under the mandates of United Nations Security Council Resolutions 82, 83, 84, and 85. These passed while the Soviet Union was boycotting the UN for awarding China's seat in the Security Council to the Republic of China. While the UN had some military authority through Chapter VII of the United Nations Charter, early Cold War tensions meant that the forces envisaged in those articles had yet to become reality. Thus the UN had little practical ability to raise a military force in response to the North Korean invasion of the South. Consequently, the UNSC designated the United States as the executive agent for leading a "unified command" under the UN flag. As it was a designated body, the UN exercised little control over the combat forces. This represented the first attempt at collective security under the UN system.
When the warring parties signed the Korean Armistice Agreement on 27 July 1953, the commander delivered the Agreement to the UN. In August 1953, the UN General Assembly passed a resolution “noting with approval” the Armistice Agreement, a step that was critical for the UN to take the next step of organizing the 1954 Geneva Conference meant to negotiate a diplomatic peace between North and South Korea. The adoption of the Korean Armistice Agreement in the UN General Assembly underwrites UN Command's current role of maintaining and enforcing the Armistice Agreement.
The role of the United States as the executive agent for the unified command has led to questions over its continued validity. Most notably, in 1994, UN Secretary General Boutros Boutros-Ghali wrote in a letter to the North Korean Foreign Minister that:
The UN's official position is that the Korean War-era Security Council and General Assembly resolutions remain in force. This was evidenced in 2013 when North Korea announced unilateral abrogation of the Armistice Agreement: UN spokesman Martin Nesirky asserted that since the Armistice Agreement had been adopted by the General Assembly, no single party could dissolve it unilaterally. The UNC continues to serve as the signatory and party of the Armistice opposite the Korean People's Army.
In JENNINGS v. MARKLEY, WARDEN, a determination was made by the Court of Appeals Seventh Circuit that American soldiers of the UNC were still liable to the Uniform Code of Military Justice although they fought under the UN blue flag.

Establishment in 1950

After troops of North Korea invaded South Korea on 25 June 1950, the United Nations Security Council adopted Resolution 82 calling on North Korea to cease hostilities and withdraw to the 38th parallel.
Two days later, the UNSC adopted Resolution 83, recommending that members of the United Nations provide assistance to the Republic of Korea "to repel the armed attack and to restore international peace and security to the area".
The first non-Korean and non-U.S. unit to see combat was the No. 77 Squadron of the Royal Australian Air Force, which began escort, patrol and ground attack sorties from Iwakuni Royal Australian Air Base, Japan on 2 July 1950. On 29 June 1950, New Zealand made preparations to dispatch two Loch class frigates, and, to Korean waters; on 3 July, the ships left Devonport Naval Base, Auckland and joined other Commonwealth forces at Sasebo, Japan on 2 August. For the duration of the war, at least two NZ vessels would be on station in the theater.
Resolution 84, adopted on 7 July 1950, recommended that members providing military forces and other assistance to South Korea "make such forces and other assistance available to a unified command under the United States of America".
President Syngman Rhee of the Republic of Korea assigned operational command of ROK ground, sea, and air forces to General MacArthur as Commander-in-Chief UN Command on 15 July 1950:
On 29 August 1950, the British Commonwealth's 27th Infantry Brigade arrived at Busan to join UNC ground forces, which until then included only ROK and U.S. forces. The 27th Brigade moved into the Naktong River line west of Daegu.
Units from other countries of the UN followed: the Belgian United Nations Command, the 25th Canadian Infantry Brigade, the Colombian Battalion, the Ethiopian Kagnew Battalion, the French Battalion, the Greek 15th Infantry Regiment, New Zealand's 16th Field Regiment, Royal New Zealand Artillery, the Philippine Expeditionary Forces to Korea, the South African No. 2 Squadron SAAF, the Turkish Brigade, and forces from Luxembourg and the Netherlands. Additionally, Denmark, India, Iran, Norway and Sweden provided medical units; Italy provided a hospital, even though it was not a UN member at the time.
By 1 September 1950, less than two months before the formation of United Nations Command, these combined forces numbered 180,000, of which 92,000 were South Koreans, with most of the remainder being Americans, followed by the 1,600-man British 27th Infantry Brigade.
Rockoff writes that "President Truman responded quickly to the June invasion by authorizing the use of U.S. troops and ordering air strikes and a naval blockade. He did not, however, seek a declaration of war, or call for full mobilization, in part because such actions might have been misinterpreted by Russia and China. Instead, on July 19 he called for partial mobilization and asked Congress for an appropriation of $10 billion for the war." Cohen writes that: "All of Truman's advisers saw the events in Korea as a test of American will to resist Soviet attempts to expand their power, and their system. The United States ordered warships to the Taiwan Strait to prevent Mao's forces from invading Taiwan and mopping up the remnants of Chiang Kai-shek's army there."
As of 1 July 1957 the commander of the United Nations Command was "triple hatted" being given command the United States Forces Korea and Eighth United States Army in addition to the UN command. The first commander to be "triple hatted" in this way was General George Decker, who would later serve as the Chief of Staff of the United States Army.

Commander

Deputy Commander

Current membership

During the three years of the Korean War, the following nations were members of the UNC. By 27 July 1953, the day the Armistice Agreement was signed, UNC had reached a peak strength of 932,964:
During the course of the war, UNC was led by Douglas MacArthur, Matthew B. Ridgway, and Mark Wayne Clark. After the armistice was signed, John E. Hull was named UNC commander to carry out the ceasefire.