Unilateral declaration of independence

This article is about unilateral declarations of independence in general. For the Rhodesian declaration of 1965, see Rhodesia's Unilateral Declaration of Independence. For the British declaration concerning Egypt, see Unilateral Declaration of Egyptian Independence.

A unilateral declaration of independence (UDI) or "unilateral secession" is a formal process leading to the establishment of a new state by a subnational entity which declares itself independent and sovereign without a formal agreement with the state from which it is seceding. The term was first used when Rhodesia declared independence in 1965 from the United Kingdom (UK) without an agreement with the UK.

Examples

Prominent examples of a unilateral declaration of independence other than Rhodesia's UDI in 1965 include that of the United States in 1776, the Irish Declaration of Independence of 1919 by a revolutionary parliament, Katanga's declaration of independence by Moise Tshombe in July 1960, the attempted secession of Biafra from Nigeria in 1967, the Proclamation of Bangladeshi Independence from Pakistan in 1970, the (internationally unrecognized) secession of the Turkish Republic of Northern Cyprus from Cyprus in 1983, the Palestinian Declaration of Independence from the Palestinian territories in 1988, and that of the Republic of Kosovo in 2008. During the Dissolution of the Soviet Union throughout 1991, many of its republics declared their independence unilaterally without agreement and were thus not recognised as legitimate by the Soviet Central Government.

During the breakup of Yugoslavia, the government of the United States asked the governments of Croatia and Slovenia to drop their UDI plans because of the threat of major war erupting in the Balkans because of it, and threatened that it would oppose both countries' UDIs on the basis of the Helsinki Final Act if they did so. However, four days later both Slovenia and Croatia announced their UDIs from Yugoslavia.

Date Declared state Parent state International recognition Notes
1776 United States Great Britain Yes
1777 Vermont Great Britain Yes Vermont signed a separate armistice with Britain in 1781 before the surrender of Cornwallis at Yorktown. Effective retroactive recognition by the United States was granted in 1791 when Vermont became the 14th state.
1816 Río de la Plata Spain Yes, after the military victory Division and dismembration of the independent country. Paraguay secession. Brazil invaded Uruguay. Spain recognized Argentine Independence in 1859
1821 Greece Ottoman Empire Yes Intervention by France, Russia, and the United Kingdom in favour of Greece in the Greek War of Independence secured its independence in 1832.
1830 Belgium United Netherlands Yes UDI (4 October 1830) recognized by the major European powers following the London Conference of 20 December 1830
1898 Philippines Spain No Conquered by United States; became independent in 1946 by agreement
1903 Panama Colombia Yes
1912 Albania Ottoman Empire Yes
1919 Irish Republic United Kingdom Yes
1922 Kingdom of Egypt United Kingdom Yes Unilateral grant of independence by the British government
1931 Jiangxi China No
1945 Indonesia Netherlands Yes
1960 Katanga Republic of the Congo No Breakaway Congolese province, secession forcibly ended by the United Nations Operation in the Congo in 1963.
1965 Rhodesia United Kingdom No Self-governing British colony, unilaterally declared itself independent as Rhodesia in 1965, renamed Zimbabwe Rhodesia 1979, then gained international recognition as Zimbabwe in 1980.
1967 Anguilla United Kingdom No Returned as a British Crown Colony in 1969.
1967 Biafra Nigeria Partial Recognized by five countries. Present-day Nigeria
1971 Bangladesh Pakistan Yes
1973 Guinea-Bissau Portugal Yes
1975 Cabinda Angola No Present-day Angola
1975 East Timor Portugal No Shortly following the declaration of independence, the territory was invaded and annexed by Indonesia. A referendum in 1999 led to eventual independence in 2002.
1983 Northern Cyprus Cyprus Partial Still claimed by Cyprus, and recognized as such by all UN member-states except for Turkey.
1988 Palestine Israel Partial Claims territories occupied by Israel since 1967
Israeli–Palestinian conflict and peace process still ongoing
See: International recognition of the State of Palestine
1990 Namibia South Africa Yes
1990 Transnistria Moldova No Still claimed by Moldova
1990 Karakalpakstan Uzbekistan No Incorporated into Uzbekistan in 1993.
1991 Somaliland Somalia No Still claimed by Somalia
1991 Croatia Yugoslavia Yes Set off Croatian War of Independence
1991 Slovenia Yugoslavia Yes Set off Ten-Day War
1992 Bosnia and Herzegovina Yugoslavia Yes Set off Bosnian War
1991 Republic of Ichkeria Russia Partial Present-day Chechen Republic, part of Russia. Retroactively recognized by Ukraine in 2022
1991 Nagorno-Karabakh Azerbaijan No Still claimed by Azerbaijan. Recognized by 3 other post-Soviet breakaway states
1991 South Ossetia Georgia Partial Still claimed by Georgia. Recognized by 5 UN member-states.
1999 Abkhazia Georgia Partial Still claimed by Georgia. Recognized by 5 UN member-states.
2008 Kosovo Serbia Partial Still claimed by Serbia
A United Nations General Assembly (UNGA) resolution adopted on 8 October 2008 backed the request of Serbia to seek an International Court of Justice advisory opinion on Kosovo's declaration of independence. On 22 July 2010, the ICJ ruled that the declaration of independence of Kosovo "did not violate any applicable rule of international law", because its authors, who were "representatives of the people of Kosovo", were not bound by the Constitutional Framework (promulgated by UNMIK) or by UNSCR 1244 that is addressed only to United Nations member states and organs of the United Nations.
See: International recognition of Kosovo
2014 Crimea Ukraine No Annexed by Russia; still claimed by Ukraine
2014 Donetsk People's Republic
Luhansk People's Republic 		Ukraine No Annexed by Russia; still claimed by Ukraine
2017 Catalonia Spain No Spanish sovereignty remained unchanged

Legal aspects

The International Court of Justice, in a 2010 advisory opinion, declared that unilateral declarations of independence were not illegal under international law.

See also