# Unilateral declaration of 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. |
| 1813 | Cundinamarca | Spain | No | No other nation besides Venezuela, itself an unrecognised government at the time, recognised the independence of Cundinamarca. The nation was later incorporated by military force into the United Provinces of New Granada in 1814. |
| 1813 | New Granada | Spain | No | No other nation besides Venezuela, itself an unrecognised government at the time, recognised the independence of New Granada. The nation would later join together with Venezuela to form the Republic of Colombia. |
| 1816 | Río de la Plata | Spain | Yes, after the military victory | Division and dismembering of the independent country. Paraguay secession. Brazil invaded Uruguay. Spain recognized Argentine Independence in 1859. |
| 1819 | Colombia | Spain | Yes | Initially recognised by the United States (1822), the United Kingdom (1825), the Netherlands (1829) and various other Hispanic American nations between 1822 and 1831. Recognised by Spain in 1881. |
| 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 | No | Became the Irish Free State upon the ratification of the Anglo-Irish Treaty. |
| 1920 | East Karelia | Russia | Partial | Recognized only by Finland |
| 1921 | Baranya–Baja | Hungary | No | |
| 1921 | Mirdita | Albania | Partial | Recognized only by Greece |
| 1922 | Kingdom of Egypt | United Kingdom | Yes | Unilateral grant of independence by the British government |
| 1931 | Jiangxi | China | No | |
| 1931 | Catalonia | Spain | No | Spanish sovereignty remained unchanged |
| 1938 | Carpatho-Ukraine | Czechoslovakia | No |
| 1941 | Ukraine | Soviet Union | 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 | |
| 1971 | West Papua | Indonesia | No | |
| 1973 | Guinea-Bissau | Portugal | Yes | |
| 1975 | North Solomons | Australia | No | Present-day Autonomous Region of Bougainville, Papua New Guinea |
| 1975 | Cabinda | Portugal | 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 |
| 1988 | West Papua | Indonesia | No | |
| 1990 | Namibia | South Africa | Yes | |
| 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 |
| 1991 | Republic of Ichkeria | Soviet Union | Partial | Present-day Chechen Republic, part of Russia. Retroactively recognized by Ukraine in 2022 |
| 1991 | Transnistria | Moldova | Partial | Still claimed by Moldova, recognized by 2 partially unrecognised breakaway states South Ossetia and Abkhazia (+ the former Nagorno-Karabakh Republic). |
| 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. |
| 1992 | Bosnia and Herzegovina | Yugoslavia | Yes | Set off Bosnian War |
| 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 | Partial | Annexed by Russia; still claimed by Ukraine. Recognized only by 7 UN member states. |
| 2014 | Donetsk People's Republic Luhansk People's Republic | Ukraine | Partial | Annexed by Russia; still claimed by Ukraine. Recognized only by 8 UN member states. |
| 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.