United Nations Operation in the Congo
The United Nations Operation in the Congo (French: Opération des Nations Unies au Congo, abbreviated to ONUC) was a United Nations peacekeeping force deployed in the Republic of the Congo in 1960 in response to the Congo Crisis. ONUC was the UN's first peacekeeping mission with significant military capabilities and remains one of the largest UN operations in size and scope.[1]
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Following its independence from Belgium on 30 June 1960, the Congo descended into chaos and disorder, prompting its former colonial power to invade under the pretext of restoring order and protecting Belgian nationals.[2] In response to the Congolese government's appeal for assistance, on 14 July 1960 the United Nations Security Council passed Resolution 143 (S/4387) calling upon Belgium to withdraw its troops and authorizing the Secretary-General to provide the Congolese government with military assistance. The first UN troops, drawn mostly from African and Asian states, reached the Congo the following day.[3]
In the face of worsening conditions—including an insurrection in Katanga, the assassination of Prime Minister Patrice Lumumba, the collapse of the central government, and the intervention of foreign mercenaries—ONUC's initial mandate gradually expanded to include protecting the territorial integrity and political independence of the Congo, preventing an impending civil war, and securing the removal of all unauthorized foreign armed forces.[4][5][6]
At its peak, UN forces numbered nearly 20,000 military personnel from over two dozen countries, led largely by India, Ireland, and Sweden.[7] During the peak of hostilities between September 1961 and December 1962, ONUC transitioned from a peacekeeping to a military force, engaging in several clashes and offensives against secessionist and mercenary forces. Following the reintegration of Katanga in February 1963, ONUC was gradually phased out, and civilian aid increased, becoming the single largest assistance effort by the UN up to that time.[2] UN personnel were withdrawn entirely on 30 June 1964.