Since it's inception in 1945 to replace the ineffective League of Nations, the United Nations has authorized 71 peacekeeping operations as of the end of 2017.

These do not include interventions authorized by the UN like the Korean War and the Gulf War.

The 1990s saw the most UN peacekeeping operations to date, with 37 operations undertaken in that decade.

Two of them are still ongoing:

a. UN Mission for the Referendum in Western Sahara, which was commenced in 1991

b. UN Interim Administration Mission in Kosovo, which was commenced in 1999.

Peacekeeping operations are overseen by the Department of Peacekeeping Operations (DPKO) and share some common characteristics, namely the inclusion of a military or police component, often with an authorization for use of force under Chapter VII of the Charter of the United Nations.

Peacekeeping operations are distinct from special political missions (SPMs), which are overseen by the Department of Political Affairs (DPA).

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