(as of 1923). . • — The
Grand Duchy of Finland declares its
full independence from the
collapsing Russian Empire. • —
Ukraine,
Belarus,
Poland,
Latvia,
Lithuania,
Estonia,
Georgia,
Armenia and
Azerbaijan declare their independence from the
Russian Empire. The Kingdom of Serbs, Croats, and Slovenes (later known as the
Kingdom of Yugoslavia) is formed.
Denmark and
Iceland sign the
Danish–Icelandic Act of Union, which establishes the
Kingdom of Iceland as a sovereign state in a personal union with Denmark. • 1919–20 — After the dissolution of
Austria-Hungary, the fates of the successor states are decided by the
Treaty of Saint-Germain signed September 10, 1919, and by the
Treaty of Trianon signed June 4, 1920, respectively. This results in
Austria and
Hungary with reduced borders, while
Czechoslovakia is formed from their former territories. Other territories of the former monarchy are additionally awarded to
Italy,
Poland,
Romania and the newly formed
Kingdom of Serbs, Croats and Slovenes. In 1919,
Germany suffered substantial territorial losses in the
Treaty of Versailles.
Belgium receives
Neutral Moresnet and
three German cantons as compensation for extensive damage during World War I. These three cantons still form the
German-speaking community of Belgium: Eupen, Malmedy and Sankt Vith.
Denmark receives
Northern Schleswig from Germany (with local
plebiscites concluding in 1920). Most of the Prussian provinces of
Posen and of
West Prussia go to Poland. The east part of
Upper Silesia and the area of
Soldau in
East Prussia are annexed to Poland as well.
Danzig and
Saarland fall under the control of the
League of Nations. The
Memel territory comes under a temporary
French administration. • —
Greece is promised most of eastern
Thrace as well as
Ionia with the city of
İzmir (
Smyrna) in the
Treaty of Sèvres.
Soviet Russia invades and occupies
Azerbaijan.
Soviet Russia recognizes the independence of
Georgia.
Soviet Russia invades and occupies
Armenia. The
Free State of Fiume is established as a result of an Italo–Yugoslav border dispute. • — As a result of winning a
war against Soviet Russia,
Poland gains territories east of the
Curzon Line, inhabited essentially by Lithuanians, Belarusians, Poles, and Ukrainians. • —
Soviet Russia invades and occupies
Georgia. The
Treaty of Kars rearranges the borders in the
South Caucasus, considerable territories of
Georgia and
Armenia are ceded to
Turkey. • — The
Irish Free State and the
United Kingdom of Great Britain and Northern Ireland are formed from the
United Kingdom of Great Britain and Ireland. The United Kingdom maintains
Treaty Ports at
Berehaven,
Cobh, and
Lough Swilly. • — The Soviet Union is officially formed under the
Treaty on the Creation of the USSR. • — The Treaty of Sèvres is superseded by the
Treaty of Lausanne under which Greece loses its earlier territorial gains and the borders of modern
Turkey are established.
Western Thrace is ceded by
Bulgaria to
Greece, a decision earlier agreed upon in the 1919
Treaty of Neuilly-sur-Seine. On the Baltic sea, Lithuania annexes the Memel territory without plebiscite. Italian military forces take control of the Greek island of
Corfu. • — The
Treaty of Rome comes into effect, ending the existence of the Free State of Fiume and the Italo–Yugoslav border dispute. The treaty assigns Fiume (
Rijeka) to Italy and
Sušak to Yugoslavia, with joint port administration. On March 16, Italy formally annexes Fiume. • — Albania cedes territory to the Kingdom of Slovenes, Croats and Serbs. • — The
Vatican City becomes independent after the signing of the
Lateran Treaty with Italy. • —
Norway issues a royal degree annexing
Erik the Red's Land in
Greenland. • — Norway further annexes an area roughly corresponding to modern-day
King Frederick VI Coast. • — Norway returns both territories to
Denmark after the
Permanent Court of International Justice ruled against their claim on the regions. • and 2 — The remaining Polish lands are incorporated into the
Ukrainian SSR and the
Byelorussian SSR, following the approval of rigged election results by their respective
Supreme Soviets. • — The Soviet Union forces
Finland to cede various territories in the
Moscow peace treaty, ending the increasingly untenable
Winter War. • —
Eupen-Malmedy is reincorporated into Germany after the
Invasion of Belgium. • — The
Second Armistice is signed, signalling German victory over France. The terms dictate
occupation over northern and western France, while the collaborationist
French State is allowed to govern the
unoccupied lands alongside the
oversea colonies. • — The
Franco-Italian Armistice is signed, awarding Italy a
thin strip of land on the border. An additional 50 km demilitarized zone is established, in which Italian influence eventually amounts to a
de facto annexation. • — Romania is forced to give up
Bessarabia to the Soviet Union with German pressure to fulfill
their Ultimatum. • — Hungary is awarded Northern Transylvania from Romania as part of the
Second Vienna Award. • — Luxembourg and the area of
Alsace-Lorraine are put under
civil administration and attached to adjacent
Reichsgaue. While never formally incorporated, these areas were increasingly put under German Laws and are widely considered to have been fully annexed. • — The Soviet Union annexes
Lithuania after the rigged
1940 Lithuanian parliamentary elections were held. This was preceded by a long period of increasing Soviet influence and the
military occupation of the country. • — The Soviet Union annexes
Latvia in a very similar fashion to Lithuania, acceding them into one of its
constituent republics by illegitimate means following the
1940 Latvian parliamentary elections. • — The Soviet Union annexes
Estonia, once again after the respective
1940 Estonian parliamentary elections are held. • —
South Dobruja is relinquished by Romania to Bulgaria after reaching an agreement and signing the
Treaty of Craiova. • —
Balkan Campaign — At the conclusion of the
Invasion of Yugoslavia and
Greece, both countries are divided among the participants.
Yugoslavia is divided between Italy and their Albanian puppet, Germany, Hungary, Bulgaria and the newly established
Independent State of Croatia, with Montenegro falling under
Italian occupation and the rest under
German occupation.
Greece is occupied by German, Italian and Bulgarian forces, with the last directly annexing its zone. • — While the invasion is still ongoing, the
Independent State of Croatia is proclaimed by
Slavko Kvaternik. The country remains under partial joint Italian-German occupation. • — The German-occupied parts of Slovenia are put under
civil administration and attached to adjacent Reichsgaue. Similarly to Luxembourg and Alsace-Lorraine, these areas were never fully annexed, instead being set up in preparatation for eventual integration. • — The Bulgarian Occupation zone and the territory to be annexed into Italian Albania is agreed upon after multiple meetings with Germany. • — Italy issues a Royal Degree, annexing parts of Slovenia as the
Province of Ljubljana. • — Bulgaria annexes the occupied areas of Greece. • — The main
Treaty of Rome of 1941 settles the
Dalmatian territory annexed by Italy from the Independent State of Croatia. Later treaties define their borders in Ljubljana and Italian-occupied Montenegro. • — Bulgaria fully incorporates its occupied territories in Yugoslavia. As the war continues, Germany allows Bulgarian troops to occupy more territory to free up forces for the
Eastern Front. • — The
Yugoslav territories occupied by Hungary are put under civilian administration and fully integrated four months later. at the height of the Axis conquests in 1942 • — Following
Operation Barbarossa, the
Bialystok District is formed and put under Civil Administration, being attached to an adjacent Reichsgau, again in preparation for eventual annexation. It's expanded to include the city of
Grodno three months later. • — After the
liberation of Bessarabia, Romania integrates the reconquered territories as the autonomous
Bessarabia Governorate. • — Finland re-integrates the territories lost in the Moscow Peace Treaty during the
Continuation War. • —
Case Anton is executed, ending the nominal independence of
Vichy France and placing the entire country under German-Italian military administration. • — In response to the
Italian surrender, Germany executes
Operation Achse and invades their former ally, setting up a
puppet state in northern Italy. In addition to taking over all territories previously under Italian occupation, Germany splits apart lands from the Italian Social Republic, forming the Operational Zones of the
Adriatic Littoral and of the
Alpine Foothills in northeastern Italy and attaching them to adjacent Reichsgaue. • — Iceland officially declares
complete independence from Denmark. The country had been de facto independent since the
German invasion of Denmark. • — The
Moscow Armistice is signed between Finland and the Soviet Union, ending hostilities between the two countries. Finland is forced to return all territory previously ceded with the
Moscow Peace Treaty in addition to
Petsamo and a lease on
Porkkala. • — End of the War — With the total defeat of Germany, the war is finally over. All territorial changes made by the Axis Powers are fully reverted, with the notable exception of Bulgaria keeping
Southern Dobruja.
Eastern Bloc • — The borders of Germany are moved west to the
Oder-Neisse line, while the approximate boundary of the
Curzon Line is used as the eastern border of Poland. In addition to incorporating the
Kresy territories, the Soviet Union also annexed the
Baltic states,
Carpathian Ruthenia from Czechoslovakia, and
Bessarabia, the
Hertsa region, and
Northern Bukovina from Romania. From Germany, the Soviet Union acquired the northeastern third of the former East Prussian exclave with the
Klaipeda/Memel region becoming part of the
Lithuanian SSR and the bulk of the territory forming the
Kaliningrad Oblast of the
Russian SFSR. Additionally, Finland ceded major portions of
Karelia and
Salla to the Soviet Union as well as islands in the
Gulf of Finland, the whole
Petsamo, and a lease to use
Porkkala as a Soviet naval base for 50 years. • —
Saarland is separated from (occupied) Germany by France and became
a French protectorate on February 16 of that year but was not recognized by the
Allied Control Council ruling entire Germany (and Austria) so it was a
disputed territory in the
international law.
The Faroe Islands declare independence from Denmark after a
referendum. Denmark does not recognise the results and dissolves the
Faroese parliament a few days later, and hold a second referendum, which passes in favour of continued union with Denmark. • — In the
Paris Peace Treaties of 1947, Italy cedes the
Dodecanese to
Greece; La Brigue and Tende to France; 3 settlements of the
Bratislava bridgehead to
Czechoslovakia; and
Goriška,
Inner Carniola, most of
Istria,
Zadar, its
Dalmatian and
Kvarner islands (such as
Lastovo and
Cres), and Rijeka (Fiume) to the newly established
Federal Peoples' Republic of Yugoslavia.
Trieste becomes the capital city of the
Free Territory of Trieste established as an independent sovereign state at the coming into force of the treaty (September 15). • — Following the signing of the
Moscow Protocol of 1948, the Soviet Union formally annexes some Danubian islands and the
Snake Island in the Black Sea from Romania. • — The
Netherlands annexes the villages
Elten,
Tüddern and some smaller localities from Germany. • — The
Federal Republic of Germany (West Germany) is established. • — Switzerland and
Liechtenstein exchange territories in the area of Rhine-Würznerhorn. • — The
German Democratic Republic (East Germany) is established. • — Polish and Soviet
border exchange along the border of the
Ukrainian SSR. • — The
Free Territory of Trieste is dissolved and divided between Yugoslavia and Italy. • — Italy and Switzerland modify the border in the zone of
Lago di Lei • — The
Austrian State Treaty comes into force, establishing an independent
Austrian state from the four occupation zones of the Allied powers. • — The Soviet Union returns
Porkkala to
Finland. • — The
Saar Protectorate is incorporated into
West Germany as a state after the
1955 referendum. • — An adjustment to the Meuse river between
The Netherlands and
Belgium results in three small packages of land being exchanged between the two countries. • — The 1949 Dutch acquisitions of West German territory are almost completely reverted; the
Duivelsberg remains permanently with the Netherlands. • —
Malta becomes independent from the
United Kingdom. • — The
United Kingdom formally annexes
Rockall (by the
Island of Rockall Act 1972, declaring it to be part of
Scotland). Ireland does not recognise the UK's territorial claim to Rockall. • —
France and the
United Kingdom sign the
Treaty of Canterbury, defining a land frontier between the two countries. This border becomes physical with the breakthrough of the
Channel Tunnel on 1 December 1990. • — East Germany
unites with West Germany on October 3.
Transnistria declares independence from the
Moldavian SSR but is not recognised by any country. • —
Estonia,
Latvia and
Lithuania restore their independence from
Soviet occupation. With the complete
dissolution of the Soviet Union, it is split up into a further 12
independent states, including the European states of
Russia,
Belarus,
Ukraine,
Moldova,
Georgia,
Armenia and
Azerbaijan. The independence of all the former Soviet republics is recognised by December 26 (except the Baltic states, which the Soviet Union recognized on September 6).
Slovenia (June 25) including the former "zone B" of the
Free Territory of Trieste,
Croatia (June 25), and the
Republic of Macedonia (September 8) all declare their independence from
Yugoslavia. Croatia and Slovenia are formally recognized on January 15, 1992, and Macedonia in April 1993. and
Bosnia and Herzegovina in 1998 • —
Bosnia and Herzegovina declares independence from Yugoslavia on March 1 and is formally recognised on April 6. A civil war breaks out, and as the result of the war, two largely autonomous entities are formed:
Federation of Bosnia and Herzegovina and
Republika Srpska. The remaining of Yugoslavia becomes the
Federal Republic of Yugoslavia (renamed to
Serbia and Montenegro in 2003). • —
Czechoslovakia is dissolved into the
Czech Republic and
Slovakia in the "
Velvet Divorce". • 1999 June 23 —
Belgium and
The Netherlands make a small border change at the
Ghent-Terneuzen Canal. • —
Andorra and
France exchange land to allow the Andorran
Envalira Tunnel to connect to the French
RN22. • —
Lithuania's share of
Lake Vištytis increases to about 383 ha (about 22% from 2.2%) from a new border treaty with
Russia. • — The State Union of Serbia and Montenegro is dissolved following
a referendum;
Montenegro and
Serbia each become independent states. • —
Kosovo unilaterally
declares independence from
Serbia. The declaration is strongly opposed by Serbia and
recognised by just over half (101 out of 193) of UN member states. • —
Russia annexes Crimea from
Ukraine, following an internationally unrecognized
plebiscite. • —
Belgium and
the Netherlands swap land near
Lanaye and
Oost-Maarland over the discovery of a headless body several years prior, which the Belgian authorities could not access without crossing Dutch territory. The
border has been straightened out and now runs down the centre of the
Meuse River. The change took effect on 1 January 2018. ) and 2022 (
Donetsk,
Kherson,
Luhansk and
Zaporizhzhia), with a red line marking the area of actual control by Russia on 30 September 2022. • — The
State Duma of
Russia passed a bill to officially recognize the self-proclaimed
Donetsk People's Republic and
Luhansk People's Republic in
Eastern Ukraine as independent states. The bill was approved by
President Vladimir Putin.
Russia began an
invasion of
Ukraine on 24 February, in a major escalation of the
Russo-Ukrainian War that began in 2014. • — Russia
unilaterally declares the annexation of the Ukrainian oblasts of Luhansk, Donetsk, Zaporizhzhia, and Kherson. Similar to the annexation of Crimea in 2014, this border change is not recognised internationally. ==North America==