When the Korean War began in June 1950, the United States military had exactly one graves registration platoon in the entire Far East -- the 108th, stationed in Yokohama, Japan, still searching for the remains of missing World War II airmen. The only other active-duty unit was at Fort Bragg, North Carolina. As the fighting consumed the peninsula, temporary cemeteries were established near whatever town the front happened to pass through: Taejon, Kumchon, others that had to be abandoned as North Korean forces pushed south toward Busan. Eleven division-level cemeteries were established in the first two months alone, five more in North Korea after the UN counteroffensive. The dead arrived faster than the living could process them. Construction of the permanent cemetery at Tanggok began on 18 January 1951, carried out entirely by hand labor over a 28-hectare site. General Matthew Ridgway dedicated it on 6 April of that year.

Between 1951 and 1954, approximately 11,000 casualties were interred at the United Nations Military Cemetery. Graves registration units concentrated American and allied remains at Tanggok before they were permanently buried or repatriated to their home countries. The process of recovery continued even after the armistice. From September to October 1954, Operation Glory exchanged casualties between UN forces and the North Koreans, recovering 4,219 remains, of which 1,275 were non-American. In return, approximately 14,000 North Korean and Chinese remains were sent north. Seven countries eventually retrieved their dead -- Belgium, Colombia, Ethiopia, Greece, Luxembourg, the Philippines, and Thailand. The 2,300 who remain represent the nations that chose to let their soldiers rest where they fell: Australia, Canada, France, the Netherlands, New Zealand, Norway, South Africa, Turkey, the United Kingdom, and the Republic of Korea, along with American non-combatants.

The cemetery was formally established as a United Nations institution on 15 December 1955 by General Assembly Resolution 977(X). It was funded from the UN budget until the Sino-Soviet bloc objected to the expenditure, after which management was transferred in 1973 to the Commission for the United Nations Memorial Cemetery, composed of representatives from the eleven countries with soldiers buried there. Twenty-nine permanent memorials now stand on the grounds, including the Wall of Remembrance, completed in 2006, where the names of 40,896 United Nations casualties -- killed and missing -- are inscribed on 140 marble panels. The United States Korean War Memorial, a Frank Gaylord sculpture carved from Barre Granite in Vermont, was dedicated in 2013 under the auspices of the American Battle Monuments Commission. An interfaith memorial chapel, built by the United Nations Command in 1964, serves all faiths represented among the buried.

The cemetery is not a static monument. Since 2015, Korean War veterans have been officially permitted to be buried alongside their fallen comrades, and several have made that final journey. Bill Speakman, a Victoria Cross recipient who died in 2018, was interred there in 2019. The grounds include a sculpture park established in 2001, and the Unknown Soldiers' Pathway winds through the memorial landscape. South Korea has designated the site as Registered Cultural Heritage Site 359, and it draws visitors from across the Pacific Rim. When UN Secretary-General Ban Ki-moon visited in 2011, he noted its singular status -- the only place where the United Nations, an organization dedicated to preventing war, maintains a cemetery for those who died fighting one. The honor guard's daily flag ceremony, the rows of headstones catching the morning light off the Korean Sea, the sheer multinational breadth of the sacrifice recorded here -- all of it speaks to a conflict that the world has sometimes called 'the Forgotten War' but that this hillside in Busan refuses to let anyone forget.