Kosovo War: The Federal Republic of Yugoslavia and NATO sign a peace treaty.

The Kosovo War was an armed conflict in Kosovo that lasted from 28 February 1998 until 11 June 1999. It was fought between the forces of the Federal Republic of Yugoslavia (FRY), which controlled Kosovo before the war, and the Kosovo Albanian separatist militia known as the Kosovo Liberation Army (KLA). The conflict ended when the North Atlantic Treaty Organization (NATO) intervened by beginning air strikes in March 1999 which resulted in Yugoslav forces withdrawing from Kosovo.

The State Union of Serbia and Montenegro or simply Serbia and Montenegro, known until 2003 as the Federal Republic of Yugoslavia and commonly referred to as FR Yugoslavia (FRY) or simply Yugoslavia, was a country in Southeast Europe located in the Balkans that existed from 1992 to 2006, following the breakup of the Socialist Federal Republic of Yugoslavia. The state was founded on 27 April 1992 as a federation comprising the Republic of Serbia and the Republic of Montenegro. In February 2003, it was transformed from a federal republic to a political union until Montenegro seceded from the union in June 2006, leading to the full independence of both Serbia and Montenegro.

The North Atlantic Treaty Organization, also called the North Atlantic Alliance, is an intergovernmental military alliance between 32 member states—30 in Europe and 2 in North America. Founded in the aftermath of World War II, NATO was established with the signing of the North Atlantic Treaty in 1949. The organization serves as a system of collective security, whereby its independent member states agree to mutual defence in response to an attack by any external party. This is enshrined in Article 5 of the treaty, which states that an armed attack against one member shall be considered an attack against them all.

The Military Technical Agreement, also known as the Kumanovo Agreement, signed between the International Security Force (KFOR) and the Governments of the Federal Republic of Yugoslavia and the Republic of Serbia, was an accord concluded on 9 June 1999 in Kumanovo, Macedonia. It resulted in the end of the Kosovo War, and established new basic relations between Yugoslavia and the Kosovo Force, which would act to replace units of the Yugoslav Army in Kosovo.