History of United Nations peacekeeping

The United Nations Peacekeeping began in 1948. Its first mission was in the Middle East to observe and maintain the ceasefire during the 1948 Arab–Israeli War. Since then, United Nations peacekeepers have taken part in a total of 63 missions around the globe, 17 of which continue today. The peacekeeping force as a whole received the Nobel Peace Prize in 1988.

Though the term "peacekeeping" is not found in the United Nations Charter, the authorization is generally considered to lie in (or between) Chapter 6 and Chapter 7. Chapter 6 describes the Security Council's power to investigate and mediate disputes, while Chapter 7 discusses the power to authorize economic, diplomatic, and military sanctions, as well as the use of military force, to resolve disputes. The founders of the UN envisioned that the organization would act to prevent conflicts between nations and make future wars impossible; however, the outbreak of the Cold War made peacekeeping agreements extremely difficult due to the division of the world into hostile camps. Following the end of the Cold War, there were renewed calls for the UN to become the agency for achieving world peace, and the agency's peacekeeping dramatically increased, authorizing more missions between 1991 and 1994 than in the previous 45 years combined.

The League of Nations-controlled International Force in the Saar (1934–35) may be "the first true example of an international peace observation force".

Before any official peacekeeping mission, the UN played an important role in the conflict concerning Trieste after World War II. From 1947 to 1954, Trieste was declared an independent city state under the protection of the United Nations as the Free Territory of Trieste. The territory was divided into two zones, which later formed the basis for the division of the territory between Italy and Yugoslavia. The UN also authorized two nations to station troops in the Free Territory, the US (Trieste United States Troops) and the UK (British Element Trieste Force) in the northern zone and Yugoslavia in the southern zone.

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