| Date |
Event |
Historical
Background |
| January 1920 |
Soviet Russian Evacuation of Latvia |
The Latvians expelled the last Red Army troops from the country, which ensured the survival of the new republic. |
| January 1920 |
Senate Compromise Failure on Versailles Treaty |
Senator Henry Cabot Lodge's failure to support a bipartisan approach to ratification of the Treaty of Versailles effectively killed the treaty. Senator Lodge yielded to threats from the Irreconcilables and refused to modify his original reservations. |
| January 10, 1920 |
Official Opening of the League of Nations |
The League of Nations formally began operations and addressed a number of territorial issues left over from the peace treaties, as well as other issues. Under the terms of the Treaty of Versailles, the peace treaty officially took effect on this date, as well as the League of Nations Covenant. The original members of the League included Australia, Belgium, Bolivia, Brazil, the British Empire, Canada, Chile, Czechoslovakia, France, Guatemala, India Italy, Japan, New Zealand, Paraguay, Persia (Iran), Peru, Poland, Siam (Thailand), South Africa, Spain, and Uruguay. |
| January 10, 1920 |
British Mandate over Tanganyika Began |
The British government officially began their administration over the German East African mandate and changed the name of the territory to Tanganyika. The British sent the German settlers home and sold off their estates and property. |
| January 10, 1920 |
German-Japanese Peace Treaty |
The German and Japanese governments concluded a formal peace agreement with the exchange of ratifications. Although the Japanese were initially satisfied with the peace agreement, animosities arose when they realized that they did not secure recognition of Japan's special position in the Far East. |
| January 16, 1920 |
First League Council Session |
The League of Nations Council met for its first session in Paris. |
| January 16, 1920 |
Senate Rejection of the League |
The U.S. Senate voted against American participation in the League of Nations. |
| January 16, 1920 |
Argentine Admission to the League |
The League of Nations admitted the Argentine Republic as a member state of the organization. |
| January 17, 1920 |
French Presidential Elections |
Paul Deschanel defeated Georges Clemenceau in the French presidential elections. Premier Clemenceau's defeat reflected political and public opinion in France that the Treaty of Versailles was too lenient. Premier Clemenceau resigned from office the next day. |
| January 23, 1920 |
Dutch Refusal to Turn over Wilhelm II |
The Dutch government refused to turn over the former German emperor, Kaiser Wilhelm II, to Allied authorities for war crime trials. The Dutch did agree to intern the Kaiser later, at Amerongen and eventually at Doorn, and he remained in the Netherlands until his death in 1941. |
| January 28, 1920 |
Turkish Parliament Adoption of the National Pact |
The Turkish parliament in Constantinople adopted the National Pact, an annunciation of six principles drafted by the Turkish nationalists. The National Pact called for self-determination for Turkish provinces, the security of Constantinople, the opening of the Straits, the rights of minorities, and the abolishment of the capitulations. |
| January 30, 1920 |
Failed Bolshevik Coup in Vladivostok |
Bolsheviks attempted to seize control of Vladivostok in a coup, but the Japanese military intervened and prevented the Bolsheviks from gaining power. |
| February 1, 1920 |
Russo-Latvian Armistice |
The Latvian and Soviet Russian governments signed an armistice which ended the fighting between the two countries. |
| February 2, 1920 |
Treaty of Tartu (Dorpat) |
The Soviet Russian government recognized the independence of Estonia, marking the end of Estonia's participation in the Russian Civil War. |
| February 9, 1920 |
Norwegian Annexation of Spitzbergen |
The Norwegian government formally annexed the islands of Spitzbergen, which the Allied Supreme Council had awarded to Norwegian sovereignty in September 1919. |
| February 9, 1920 |
Senate Reconsideration of Versailles Treaty |
The Senate voted to reconsider the Treaty of Versailles and sent it back to the Foreign Relations Committee. The committee returned the treaty to the Senate the next day with the reservations intact. Despite the Senate's strong stand, President Woodrow Wilson refused to yield on the issue of revising the treaty. |
| February 10, 1920 |
Schleswig Northern Zone Plebiscite |
Voters in the northern zone of the North Schleswig plebiscite (74 percent) decided for reunion with Denmark. |
| February 10, 1920 |
Serb-Croat-Slovene Admission to the League |
The League of Nations admitted the Kingdom of the Serbs, Croats, and Slovenes (Yugoslavia) as a member state in the organization. |
| February 11, 1920 |
League Administration of Danzig |
The League of Nations took over the administration of the Free State of Danzig from Germany. |
| February 11-12, 1920 |
Second League Council Session |
The League of Nations Council held its second session in London. |
| February 12, 1920 |
Allied Occupation of Upper Silesia |
Due to fighting between the Germans and the Poles, the Allied Commission of Control took over administration of Upper Silesia with the support of French occupation troops. |
| February 15, 1920 |
Allied Occupation of Memel |
Allied forces occupied the Memel district and placed the port under Allied control. |
| February 15, 1920 |
Lansing Resignation as Secretary of State |
Robert Lansing resigned as the U.S. Secretary of State and was replaced by Bainbridge Colby. |
| February 16, 1920 |
Colombian Admission to the League |
The League of Nations admitted Colombia as a member state of the organization. |
| February 25, 1920 |
Romanian Evacuation from Hungary |
The last Romanian troops departed Hungary, ending a long and costly occupation. |
| February 26, 1920 |
League Administration of the Saar |
The League of Nations took over the administration of the Saar from Germany for fifteen years. At the end of this period, the League would hold a plebiscite to determine the future of the region. |
| February 29, 1920 |
Czechoslovak Constitution Adopted |
The Czechoslovaks ratified a national constitution which was closely modeled on the French constitution. |
| March 1, 1920 |
Hungarian Regency |
After overthrowing the Communist government of Bela Kun in August 1919, the monarchist provisional government appointed Admiral Nicholas Horthy, commander-in-chief of the armed forces, as head of state and regent of Hungary. |
| March 2, 1920 |
Romanian Armistice with Russia |
The Romanian and Soviet Russian governments signed an armistice ending their war over control of Bessarabia. The Romanians maintained control over the disputed province, while the Soviets faced other threats from the White Russian forces. |
| March 3, 1920 |
Venezuelan Admission to the League |
The League of Nations admitted Venezuela as a member state to the organization. |
| March 5, 1920 |
Treaty of Berlin |
The German and Latvian governments signed a treaty of friendship and cooperation. |
| March 6, 1920 |
Italo-Yugoslav Conference on Fiume |
After the Italian filibustering expedition, led by Gabriele D'Annunzio, seized control of Fiume, the governments of Italy and the Kingdom of the Serbs, Croats, and Slovenes met to solve this issue. The two governments reached a compromise in the Treaty of Rapallo on November 12th. |
| March 8, 1920 |
Danish Admission to the League |
The League of Nations admitted Denmark as a member state in the organization. |
| March 8, 1920 |
Cuban Admission to the League |
The League of Nations admitted Cuba as a member state in the organization. |
| March 8, 1920 |
Swiss Admission to the League |
The League of Nations admitted Switzerland as a member state in the organization. |
| March 8, 1920 |
Syrian Declaration of Independence |
The Syrian National Congress again declared for complete independence from France. |
| March 8, 1920 |
Wilson's Opposition to Senate Revisions |
President Woodrow Wilson reiterated his opposition to the U.S. Senate rewriting the Treaty of Versailles. |
| March 9, 1920 |
Dutch Admission to the League |
The League of Nations admitted the Netherlands as a member state in the organization. |
| March 9, 1920 |
Norwegian Admission to the League |
The League of Nations admitted Norway as member state in the organization. |
| March 9, 1920 |
Swedish Admission to the League |
The League of Nations admitted Sweden as a member state in the organization. |
| March 9, 1920 |
Proclamation of the Republic of Sonora |
Mexican Generals Adolfo de la Huerta, Alvaro Obregon, and Plutarco Elias Calles joined forces against the government of Venustiano Carranza and proclaimed the Republic of Sonora, launching another Mexican civil war. The opposition accused President Carranza of attempting to dictate the presidential succession. General Obregon captured Mexico City on May 8th and most of the cities on the east coast. President Carranza was killed on May 21st and the government forces under General Pancho Villa surrendered on July 27th, ending the civil war. |
| March 10, 1920 |
Salvadoran Admission to the League |
The League of Nations admitted El Salvador as a member state in the organization. |
| March 10, 1920 |
Egyptian Legislature Call for Independence |
The Egyptian legislative assembly passed a resolution demanding independence from Britain. |
| March 11, 1920 |
King Faisal of Syria Proclaimed |
The Arabs proclaimed Faisal the King of Syria and the British and French governments recognized his throne. |
| March 12-13, 1920 |
Third League Council Session |
The League of Nations Council held its third session in Paris. |
| March 13-17, 1920 |
Kapp Putsch in Germany |
Monarchists attempted to seize control of the German government, focusing the republican government under Gustav Bauer to flee to Stuttgart. The monarchist movement collapsed, however, due to a general strike by the trade unions. |
| March 14, 1920 |
Schleswig Southern Zone Plebiscite |
Voters (80 percent) in the southern zone of the North Schleswig plebiscite chose to remain part of Germany. |
| March 16, 1920 |
Tacna-Arica Dispute |
The Bolivian government raised the issue that neither Chile nor Peru were entitled to the disputed provinces of Tacna-Arica. The Bolivians insisted that their republic had the right to access to a port on the Pacific Ocean, preferably at
Arica. |
| March 16, 1920 |
Allied Occupation of Constantinople |
In an effort to prevent the spread of Turkish nationalism, General Sir George Milne and an Allied force occupied Constantinople, although they assured the Turks they had no intention of taking over the government. The Allies sought to keep the Straits open and to protect the Armenians. The Allies persuaded the Ottoman government to denounce the Turkish nationalists and sent many into exile. The Sultan also established a new government under Damad
Ferid. |
| March 19, 1920 |
Senate Rejection of Versailles Treaty |
The Democrats deserted President Woodrow Wilson and joined the moderate Republicans on a vote on the Lodge reservations. The U.S. Senate refused to ratify the Treaty of Versailles with reservations by a vote of 49-35, which technically continued hostilities between the United States and Germany. |
| March 19-April 3, 1920 |
Spartacist Revolt in the Ruhr |
The Communists again attempted to seize control of Germany with the Spartacists leading a major revolt in the Ruhr, the industrial heart of Germany. The German government sent in troops and ended the revolt on April 3rd in a bloody confrontation. |
| March 23, 1920 |
Proclamation of Hungarian Monarchy |
Admiral Nicholas Horthy declared Hungary a monarchy, with a vacant throne. |
| March 27, 1920 |
Wrangel Assumption of White South Russian Command |
When the Red Army captured the last White Russian base in the Ukraine, General Anton Denikin turned over the command of the White Russian forces in South Russia to General Peter
Wrangel. |
| March 27, 1920 |
Polish Territorial Demand in Belarus |
The Polish government demanded that the Soviet Russian government recognize the Polish boundaries of 1772, with a plebiscite in the territory west of that border. The Bolshevik government would not accept these terms, but expressed an interest in reaching a compromise. The breakdown in negotiations led to the Russo-Polish War which began in April. |
| March 27-April 28, 1920 |
Soviet Russian Offensive in South Russia |
After capturing the last White Army bases in the Ukraine, outside of the Crimea in late April, the Red Army advanced into the Caucasus, taking Baku on April 28th. The Red Army gains were short-lived as the White Russians mounted another offensive in South Russia. |
| March 30, 1920 |
Greek Admission to the League |
The League of Nations admitted Greece as a member state of the organization. |
| April 6, 1920 |
Establishment of the Far Eastern Republic |
In an effort to avoid a war with the Japanese without yielding control of eastern Siberia, the Soviet Russian government set up the Far Eastern Republic as a buffer state with the capital in Chita. The Soviets maintained the fiction of an independent Far Eastern Republic until the Japanese evacuated Vladivostok in October 1922. |
| April 6-May 17, 1920 |
French Occupation of the Ruhr |
In response to the German army intervention against the Spartacists in the Ruhr, the French sent forces to occupy Frankfurt and other cities in the region. In effect, the French seized the industrial and economic center of Germany and the intervention served as a rehearsal for the Franco-Belgian occupation of January 1923. |
| April 8, 1920 |
Portuguese Admission to the League |
The League of Nations admitted Portugal as a member state of the organization. |
| April 9-11, 1920 |
Fourth League Council Session |
The League of Nations Council held its fourth session in Paris. |
| April 11, 1920 |
Dissolution of the Turkish Parliament |
To prevent continued nationalist agitation, the Ottoman government dissolved the Turkish parliament, a body which had strong nationalist sentiments. |
| April 13-17, 1920 |
International Health Conference |
The League of Nations hosted the International Health Conference in London to improve international health standards and practices. |
| April 18-26, 1920 |
San Remo Conference |
The Allied prime ministers met in San Remo to discuss a number of territorial problems, including the general framework of the Turkish peace treaty. The Allies agreed to leave the Fiume question up to the governments of Italy and the Kingdom of the Serbs, Croats, and Slovenes. The delegates also considered ways of disposing of Class A mandates. Under the League of Nations system, Class A mandates were in the final stages of preparation for independence. |
| April 23, 1920 |
Provisional Nationalist Turkish Government |
General Mustapha Kemal and the Nationalists set up a provisional government in Ankara (Angora) to challenge the Ottoman government in Constantinople. |
| April 25, 1920 |
Soviet Russian-Turkish Nationalist Military Agreement |
The Nationalist Turkish government in Ankara signed a military agreement with the Soviet Russians in which the Soviets provided military supplies to the nationalist forces. |
| April 25, 1920 |
Palestinian Mandate to Britain |
The Supreme Council assigned the mandates of Palestine and Transjordania to Britain on the terms set forth in the Balfour Declaration. An exception was made in terms of the provisions of the establishment of a Jewish homeland to
Transjordania. |
| April 25, 1920 |
Iraqi Mandate to Britain |
The Supreme Council assigned the mandate of Iraq (Mesopotamia) to Britain. |
| April 25, 1920 |
Syrian Mandate to France |
The Supreme Council assigned the mandate of Syria to France. |
| April 25-October 25, 1920 |
Russo-Polish War |
The ousted Ukrainian government of Simon Petliura negotiated an alliance with the Polish government to oust the Bolsheviks from the Ukraine. The Polish army launched a major offensive on April 25th and quickly overran the country. The Poles sought to reestablish the 1772 borders of Poland and seized Kiev on May 7th. |
| April 30, 1920 |
End of British Conscription |
The British government abolished conscription into the kingdom's armed forces, restoring the volunteer army. |
| May 1920 |
Teschen Disorders |
Fighting between the Polish and Czechoslovak populations in Teschen continued after the Czechoslovaks occupied the former duchy. An Allied plan for a plebiscite did not restore order in the province. |
| May 1, 1920 |
Latvian Constituent Assembly |
The Latvian Constituent Assembly met and drafted a constitution for the new republic. |
| May 1, 1920 |
Belgium-Luxembourg Customs Union |
The governments of Belgium and Luxembourg established a customs union between the two countries. Luxembourg had been part of the German Zollverein until 1919. |
| May 5, 1920 |
British Acceptance of Iraqi Mandate |
The British government officially accepted the Iraqi mandate from the League of Nations. |
| May 10, 1920 |
Canadian Minister in Washington |
The Canadian government announced that it would send a resident minister to Washington, DC to represent Canadian interests. This represented a new international status for Canada as the government took the first step to taking over the dominion's foreign affairs. |
| May 14-19, 1920 |
Fifth League Council Session |
The League of Nations Council held its fifth session in Rome. |
| May 15, 1920 |
British Reinforcements in Ireland |
With the outbreak of the civil war between Sinn Fein and British troops, the British government dispatched reinforcements (the Black and Tans) to Ireland to restore order. The British also instituted the policy of reprisal which led to several months of serious conflict. |
| May 18-August 24, 1920 |
Soviet Russian Offensive in Northern Persia |
The Soviet Russian fleet, having defeated the White Russian forces, seized Enzeli and Resht and occupied most of Gilan. The Bolsheviks established the Soviet Republic of Gilan, which remained in power until October 1921. |
| May 20, 1920 |
Congressional Termination of War with Germany |
The U.S. Congress passed a joint resolution ending the war between the United States and Germany. President Woodrow Wilson vetoed the resolution. |
| June-October 1920 |
White Russian Offensive in South Russia |
General Peter Wrangel launched a major offensive in the region north of the Sea of Azov and overran much of southern Russia. The White Russian offensive coincided with the Polish invasion of the Ukraine, which diverted Red Army units from southern Russia. |
| June 4, 1920 |
Treaty of Trianon |
With the evacuation of Romanian troops and renewed political stability, the Allies resumed their peace negotiations with the Hungarians which led to the signing of the Treaty of Trianon. Under the treaty, Hungary lost three-quarters of its pre-war territory and two-thirds of its inhabitants. The Hungarians ceded Slovakia to Czechoslovakia; Western Hungary to Austria; Croatia-Slavonia and part of the Banat of Temesvar to the Kingdom of the Serbs, Croats, and Slovenes; and the remainder of the Banat of Temesevar, Transylvania, and part of the Hungarian plain to Romania. The Hungarians agreed to pay reparations to the Allies, maintain an army of only 35,000 men, turn over war criminals, and assume part of the imperial Austro-Hungarian debt. |
| June 5, 1920 |
Ugandan Government Reorganization |
The British reorganized the Ugandan government, establishing a nominated legislative council. |
| June 6, 1920 |
Reestablishment of German Reichstag |
The Germans held national elections to replace the National Assembly with a regular Reichstag. The Weimar coalition lost its majority in the elections to a new coalition formed by the People's Party (Liberal), Center, and Democrats. |
| June 7-November 9, 1920 |
Anglo-Egyptian Talks in London |
Saad Zaghul Pasha, leader of the Egyptian nationalists, traveled to London to conduct negotiations with Sir Alfred Milner regarding the independence of Egypt. The British had a vested interest in the control and defense of the Suez Canal and sought to maintain their interest in an independent Egypt. |
| June 10, 1920 |
Presentation of the Treaty of Sevres to the Turks |
The Allied Powers presented the Treaty of Sevres to the Turkish government. Sultan Mohammed VI protested vigorously against the draconian terms and the Nationalists received even greater popular support for their movement. |
| June 11-August 14, 1920 |
Soviet Russian Counter-Offensive against Poland |
The Red Army launched a sudden counter-offensive against the Polish-Ukrainian army in June and forced the Poles into a general retreat. The Red Army captured Kiev on June 15th and Vilna on July 15th. The Red Army then drove deep into Polish territory and placed Warsaw under siege on August 14th. The international community expected the Polish government to collapse in the face of the Bolshevik onslaught. |
| June 14-16, 1920 |
Sixth League Council Session |
The League of Nations Council held its sixth session in London. |
| June 15, 1920 |
Danish Administration in North Schlesvig |
The Danish government assumed control over the northern zone of North Schlesvig, which had voted for reunion with Denmark in the plebiscite. |
| June 15-July 10, 1920 |
Second International Labor Organization Conference |
The International Labor Organization (BIT) conducted its second session in Genoa under the chairmanship of Baron Mayor des Planches (Italy). The delegates addressed a wide range of issues including minimum age for sailors, unemployment indemnity for shipwrecked sailors, and the employment of seamen. |
| June 19-22, 1920 |
Conferences of Hythe and Boulogne |
Allied delegates met in Hythe and Boulogne to discuss the deteriorating situation in Turkey and reparations problems. Turkish nationalists proved to be gaining strength and challenged the Greek and Italian spheres of influence in Anatolia. The Allies agreed on the German reparations plan composed of 42 annual payments. Germany's bleak economic situation also threatened the reparations program that the Allies depended on for reconstruction. |
| June 22-July 25, 1920 |
Greek Offensive in Anatolia |
The Greek army began its offensive in Anatolia from Smyrna to establish a sphere-of-influence in western Turkey. British Prime Minister David Lloyd-George strongly encouraged the Greeks to mount the offensive as the quickest means to force the Turkish government to sign the peace treaty. The Greeks defeated the Turks at Alashehr on June 24th, seized Brusa on July 9th, and captured Adrianople on July 25th, the key Turkish fortress in Thrace. |
| June 28, 1920 |
Democratic Convention and the Versailles Treaty |
President Woodrow Wilson urged the delegates at the Democratic National Convention at San Francisco to make the election a "solemn referendum" for the ratification of the Versailles Treaty. The Democrats adopted a party platform which pledged unequivocal ratification of the Treaty of Versailles with only such reservations as were necessary under the U.S. Constitution. The Democratic presidential candidate, James M. Cox, publicly promised that as soon as he was sworn into office, the U.S. would enter the League of Nations. |
| June 30, 1920 |
Haitian Admission to the League |
The League of Nations admitted Haiti as a member state to the organization. |
| June 30, 1920 |
Liberian Admission to the League |
The League of Nations admitted Liberia as a member state to the organization. |
| July-December 1920 |
Great Arab Insurrection in Iraq |
Arab nationalists in Iraq mounted a massive insurrection against British rule in the mandate. The Arabs besieged several British garrisons for weeks before the British could suppress the movement. This was the first major demonstration of Arab nationalism in opposition to British rule. |
| July 5-16, 1920 |
Spa Conference |
German delegates to the conference introduced a plan for reparations payments and signed a disarmament engagement. The Allied governments decided to distribute the German reparations payments on the following formula: France received 52 percent of the payment; the British Empire 22 percent; Italy 10 percent; Belgium 8 percent; and the smaller powers received the remainder. The Germans arranged for coal deliveries to help meet their reparations payments as well as a protocol of disarmament. |
| July 9, 1920 |
Incorporation of Northern Schlesvig into Denmark |
The Danish government officially incorporated the northern zone of North Schleswig into Denmark in response to the plebiscite of February. |
| July 9-12, 1920 |
Seventh League Council Session |
The League of Nations Council held its seventh session in London. |
| July 11, 1920 |
East Prussian Plebiscites |
Voters in Allenstein and Marienwerder participated in a plebiscite to determine their future status as Germans or Poles. The overwhelming majority in both regions (97 percent) voted to remain in union with Germany. |
| July 12, 1920 |
Treaty of Moscow |
The Soviet Russian government recognized the independence of Lithuania, marking the end of Lithuania's participation in the Russian Civil War. The Bolsheviks were at war with Poland and decided to recognize an independent Lithuania, in control of Vilna, as the best means to secure their flank on the Baltic. |
| July 15, 1920 |
Soviet Russian Occupation of Vilna |
Red Army troops regained control of Vilna from the Lithuanians, which Polish troops had evacuated as a result of the Curzon Line award. |
| July 16, 1920 |
Chinese Admission to the League |
The League of Nations admitted China as a member state of the organization. |
| July 23, 1920 |
Reorganization of Kenya |
The British government renamed British East Africa as Kenya and made the territory a crown colony. The coastal strip of the colony, leased from the Sultan of Zanzibar in 1887, became known as the Kenya Protectorate. |
| July 24, 1920 |
Treaty of St. Germain Effective |
The Treaty of St. Germain, which established the peace terms for Austria, came into force. |
| July 25, 1920 |
French Occupation of Damascus |
French forces seized Damascus where they dethroned King Faisal and forced him to flee Syria. |
| July 28, 1920 |
Division of Teschen |
To end the political disorders in Teschen, a conference of ambassadors divided the province up between Czechoslovakia and Poland. |
| July 28, 1920 |
Native Affairs Commission in South Africa |
The South African government established a Native Affairs Commission and extended the native council system to all native reservations. The native question continued to be a volatile political issue because the reservations were wholly inadequate and because a large percentage of the native population had become detribalized. They settled agricultural laborers on white farms or worked as mine or industrial workers in the larger towns. |
| July 30-August 5, 1920 |
Eighth League Council Session |
The League of Nations Council held its eighth session in San Sebastian. |
| August 1920 |
Nejd Annexation of Asir |
Abd al-Aziz ibn Saud, leader of the Wahabis of Nejd, conquered and annexed
Asir. |
| August 2, 1920 |
Italo-Albanian Agreement |
The Italian and Albanian governments signed an agreement whereby the Italians evacuated their troops from Albania with the exception of the island of Saseno. The Albanians had launched an offensive against the Italians and made the Italian position in Albania untenable. |
| August 9, 1920 |
Treaty of Neuilly Effective |
The Treaty of Neuilly, which established the peace terms for Bulgaria, came into force. |
| August 10, 1920 |
Italo-Greek Agreement |
The Italian and Greek governments signed an agreement which determined the status of territory in the eastern Mediterranean. The Italian government confirmed its cession of the Dodecanese Islands to Greece. In addition, the Italians promised to cede Rhodes to the Greeks in fifteen years if the British ceded Cyprus to Greece and a plebiscite in Rhodes resulted in a union with Greece. |
| August 11, 1920 |
Treaty of Riga |
The Soviet Russian government recognized the sovereignty of Latvia, marking the end of Latvian participation in the Russian Civil War. The Bolsheviks renounced all claims to Latvia. |
| August 14, 1920 |
Czechoslovak-Yugoslav Treaty of Alliance |
The governments of Czechoslovakia and the Kingdom of the Serbs, Croats, and Slovenes signed a treaty of alliance which became the basis for the Little Entente. The two states agreed to enforce the Treaty of Trianon to prevent Hungarian revision and a possible Hapsburg restoration. |
| August 14-16, 1920 |
Battle of Warsaw |
Marshal Josef Pilsudski, supported by French troops under General Maxime Weygand, mounted a vigorous defense of Warsaw and accomplished the "miracle of the Vistula" by breaking through the Red Army lines. The Soviet Russian defeat forced large numbers of Red Army troops to cross the East Prussian border into Germany and into internment. |
| August 16-October 12, 1920 |
Polish Fall Counter-Offensive |
The Red Army defeat at Warsaw forced the Soviet Russian armies to withdraw from Polish territory and the Polish army regained the offensive. They continued to advance to the east past the Curzon Line to reclaim parts of Belarus. |
| August 17, 1920 |
Romania Adherence to Czechoslovak-Yugoslav Treaty of Alliance |
The Romanian government signed the treaty of alliance with the governments of Czechoslovakia and the Kingdom of the Serbs, Croats, and Slovenes in an effort to prevent future Hungarian revisionism in Eastern Europe. |
| August 20, 1920 |
Treaty of Sevres |
The weak and helpless government of Sultan Mohammed VI signed the Treaty of Sevres. The Sultan's sovereignty was limited to Constantinople, where he was protected by an international occupation force. Under the terms of the Treaty of Sevres, the Ottoman government renounced all claims on non-Turkish territory. The Sultan recognized the independence of the Kingdom of the Hejaz; Syria became a French mandate; Mesopotamia (including Mosul) and Palestine became British mandates; Smyrna and surrounding territory came under Greek admininstration for five years, to be followed by a plebiscite; the Dodecanese and Rhodes became Italian territory; Thrace and the remaining Turkish Aegean islands became part of Greece; Armenia gained its independence; the Straits were internationalized and the adjoining territory became demilitarized; and only Constantinople, with the strip of territory to the Chatalja lines and Anatolia remained Turkish territory. The Turkish nationalists, under General Mustapha Kemal, refused to recognize the Treaty of Sevres. They built up their military power in Anatolia and organized a government opposed to Sultan Mohammed VI and the Allied Powers. |
| August 24, 1920 |
Lithuanian Occupation of Vilna |
The Lithuanians regained Vilna and the surrounding territory after the Red Army evacuated the city. Vilna was the largest city in Lithuania and the Lithuanians planned to make Vilna their national capital. |
| August 24, 1920 |
Persian Occupation of Resht |
The Persian Cossack Brigade, commanded by Colonel Storroselski, regained Resht from the Soviet Russians. The Persians were later defeated by the Soviets and forced to retreat from Enzeli. The British helped reorganize the battalion for future operations. |
| September 1, 1920 |
U.S.-Siamese Treaty on Extraterritorial Rights |
The U.S. and Siamese governments signed a treaty whereby the United States gave up any extra-territorial rights in Siam and granted the Siamese government tariff autonomy. |
| September 2, 1920 |
Italian Evacuation of Albania |
Under military pressure from the Albanians, Italian military forces departed the country, except for the island of Saseno, as required under the terms of the Italo-Albanian treaty of August 1920. |
| September 4, 1920 |
Romanian Admission to the League |
The League of Nations admitted Romania as a member state in the organization. |
| September 7, 1920 |
Franco-Belgian Military Convention |
The French and Belgian governments signed a military convention by which the Belgians agreed to act in close cooperation with the French in most questions of international affairs. |
| September 8, 1920 |
Indian Non-Cooperation Campaign |
The National Congress, led by Mohandas K. Gandhi, launched the first non-cooperation campaign against the British, which included a boycott against British goods. Gandhi preached the benefits of wearing homespun cloth, rather than British imports, to revive village industries. The spinning wheel became an important symbol of Indian nationalism. The movement aimed at "home rule" and supported the Muslim Khilafat movement, which protested the Allied treatment of the Turks. |
| September 16-20, 1920 |
Ninth League Council Session |
The League of Nations Council held its ninth session in Paris. |
| September 20, 1920 |
League Cession of Eupen and Malmedy |
By decision of the League of Nations, Germany ceded Eupen and Malmedy to Belgium. Five-sixths of the 600,000 inhabitants were German-speaking. The Treaty of Versailles did not provide for a plebiscite for these people, but they did have six months to register their preference publicly. |
| September 24-October 8, 1920 |
International Financial Conference |
The League of Nations hosted the International Financial Conference in Brussels to develop a new post-war international financial system. |
| September 25, 1920 |
French Organization of Syria |
The French government organized the government of the Syrian mandate, creating the states of Aleppo, Damascus, and Alaouite under a French commissioner and the autonomous state of Greater Lebanon, composed primarily of Christians. |
| October 1, 1920 |
New Austrian Constitution |
The Austrians redrew a constitution based on the Swiss federal state system composed of eight provinces (Vienna was a separate province) and a two-chamber legislature. |
| October 9, 1920 |
Polish Occupation of Vilna |
Polish freebooters, led by General Lucien Zeligowski, drove the Lithuanians out of Vilna and reclaimed the province for Poland, with the secret approval of Marshal Josef Pilsudski. The Lithuanians refused to give up their claim to Vilna and turned to the League of Nations for assistance. The League decided to schedule a plebiscite to determine the future of the province, but the vote was cancelled on March 3, 1921. Unable to make Vilna the national capital, the Lithuanians established their seat of government in Kaunas (Kovno). |
| October 10, 1920 |
Klagenfurt Plebiscite |
Voters (57 percent) in Klagenfurt (Carinthia) settled the territorial dispute between Austria and the Kingdom of the Serbs, Croats, and Slovenes by voting for continued union with Austria. |
| October 10, 1920 |
Italian Annexation of South Tyrol |
The Italian government officially incorporated South Tyrol into the Italian kingdom. |
| October 12, 1920 |
Preliminary Treaty of Riga |
The Soviet Russian and Polish governments signed an armistice in the preliminary Treaty of Riga which ended the fighting in the Russo-Polish War. The Poles were able to claim far more territory in eastern Poland than the Allies were willing to grant at the Paris Peace Conference. |
| October 14, 1920 |
Treaty of Dorpat (Tartu) |
The Soviet Russian government recognized the independence of Finland, marking the end of Finnish participation in the Russian Civil War. The Finns gained a narrow strip of territory between Murmansk and the eastern frontier of Norway which gave Finland an outlet to the Arctic Ocean at the ice-free port of Pechenga. The fate of the Finnish population in Karelia remained unresolved and continued to be a source of friction between the two countries. The Bolsheviks succeeded in pacifying their borders with their Baltic neighbors. |
| October 15-21, 1920 |
Conference on Passports and Customs Formalities |
The League of Nations hosted a conference in Paris to address the problems of passports and customs formalities for international travelers. |
| October 20, 1920 |
Treaty of Ankara |
The French and Ottoman governments signed a treaty whereby the Turks recognized the French mandate in Syria. |
| October 20-28, 1920 |
Tenth League Council Session |
The League of Nations Council held its tenth session in Brussels. |
| October 21-December 3, 1920 |
Turkish Offensive against Armenia |
Turkish nationalist forces launched an offensive against the Armenian Republic and captured Kars on October 21st. The Turks forced the Armenians to the peace table for the first revision of the Treaty of Sevres. |
| October 25, 1920 |
Italian Recognition of Sheikh Sidi Idriss |
The Italian government recognized Sheikh Sidi Idriss as the leader of the Sensussi. This recognition gave the sheikh wide authority over Kufra and other important oases in Libya. |
| October 25, 1920 |
Death of King Alexander I of Greece |
King Alexander I of Greece died, after having ruled Greece for three years. His death resulted in a regency under his wife, Queen Olga. The Allies supported King Alexander after his father, King Constantine, and the Crown Prince, both viewed as pro-German, abdicated their claims to the Greek throne. |
| October 28, 1920 |
Recognition of Romanian Control over Bessarabia |
The British, French, Italian, and Japanese governments recognized Romanian possession of Bessarabia in this agreement. The British and French did not ratify the treaty until 1924, and the Italians delayed their promulgation of the treaty until 1927. |
| October-November 14, 1920 |
Soviet Russian Fall Offensive in South Russia |
With the conclusion of the Russo-Polish War, the Red Army was able to divert forces to southern Russia to deal with the White Russian threat under General Peter Wrangel. The Red Army forced the White Russians to withdraw to their citadel in the Crimea by November 1st. The Red Army mounted a major offensive against the Crimea and overwhelmed the White Russian defenses. By November 14th, General Wrangel was forced to evacuate his army to Constantinople, ending the White Russian threat in southern Russia and the Ukraine. |
| November 1, 1920 |
Bolivian Appeal to League on Tacna-Arica Dispute |
The Bolivian government appealed in vain to the League of Nations for the organizations to resolve the dispute between Bolivia, Chile, and Peru regarding sovereignty over the Tacna-Arica provinces. The Bolivians sought League support for ocean access for their republic. |
| November 1, 1920 |
Cuban Election Challenge |
Dr. Alfredo Zayas, leader of the coalition National League, was elected as the new Cuban president by fraudulent means, according to his opponent, Jose Gomez, leader of the Liberal Party. To prevent a civil war, the Wilson administration dispatched General Enoch Crowder to investigate the situation. General Crowder arranged for new elections in March 1921, which resulted in another victory for Alfredo Zayas. |
| November 2, 1920 |
U.S. Presidential Election |
Senator Warren G. Harding, the Republican candidate, soundly defeated Governor James M. Cox in the presidential election. Senator Harding did not take a stand either way on the Treaty of Versailles and the League of Nations during the campaign, and followed through with the same policy during his term in office. |
| November 3, 1920 |
Honduran Admission to the League |
The League of Nations admitted Honduras as a member state of the organization. |
| November 3, 1920 |
Nicaraguan Admission to the League |
The League of Nations admitted Nicaragua as a member state of the organization. |
| November 9, 1920 |
Danzig Declared a Free State |
As provided in the Treaty of Versailles, Danzig became a Free State and placed under the protection of the League of Nations. |
| November 12, 1920 |
Treaty of Rapallo |
The Kingdom of the Serbs, Croats, and Slovenes and Italy signed the Treaty of Rapallo which addressed the Fiume Question. Fiume became a free state (independent city) and the Italians renounced their claims to Dalmatia (Split and Sebenico), with the exception of Zara and a number of Dalmatian Islands in the Adriatic. The Kingdom of the Serbs, Croats, and Slovenes gained Susak while Istria was divided between the two countries. |
| November 14-December 18, 1920 |
Eleventh League Council Session |
The League of Nations Council held its eleventh session in Geneva. |
| November 15-December 18, 1920 |
First League Assembly Session |
The League Assembly met for its first session, under Paul Hymans (Belgium), and began deliberations on a host of international issues. The delegates allocated mandates and established the Permanent Court of International Justice. |
| November 25, 1920 |
Panamanian Admission to the League |
The League of Nations admitted Panama as a member state of the organization. |
| November 28, 1920 |
Constituent Assembly Election in the Kingdom of Serbs, Croats, and Slovenes |
The Kingdom of the Serbs, Croats, and Slovenes held elections for a constituent assembly, but no party gained a majority. The Croats, under the leadership of Stephen Radich, refused to take their seats in the assembly until the government recognize the federal principle as the basis of the constitution. The Croat boycott gave the Serbian Centralists, led by Nicholas Pasich, a free hand in the framing of the constitution. |
| December 1920 |
Sahara Crossing by Auto |
The Courtot expedition crossed the Sahara Dessert to Lake Chad by motor car. |
| December 1920 |
U.S. Withdrawal from the Dominican Republic Plans |
President Woodrow Wilson ordered the U.S. Army to draw up plans to end the military occupation of the Dominican Republic. The U.S. began negotiations with the various political parties in preparation for a national election. |
| December 1, 1920 |
Fiume War Declaration on Italy |
Gabriele D'Annunzio, leader of the Fiume government, declared war against Italy in response to the terms of the Treaty of Rapallo. |
| December 3, 1920 |
Peace of Alexandropol |
The Turkish nationalist government and the Armenian government signed a peace treaty ending the Turco-Armenian war. The Turks regained Kars and Ardahan, leaving Armenia the province of Erivan. The Armenians ceded half of their territory to the Turks in the peace treaty. |
| December 4, 1920 |
Reorganization of French Sudan |
The French government changed the name of Upper Senegal-Niger to the French Sudan and created a superior council (which included elected seats) to govern French West Africa. |
| December 5, 1920 |
Greek Plebiscite on the Monarchy |
Despite Allied warnings, the Greek government held a plebiscite which resulted in almost unanimous support for King Constantine. The Allies forced King Constantine to abdicate in 1917 due to his pro-German sympathies. |
| December 15, 1920 |
Austrian Admission to the League |
The League of Nations admitted Austria as a member state of the organization. |
| December 15, 1920 |
Philippine Independence Funding |
The Philippine legislature passed a bill which authorized one million pesos annually to defray the costs of the Independence Commission. |
| December 15-22, 1920 |
Brussels Conference |
The Allies held another reparations meeting in Brussels and concluded that Germany would pay a total of almost 13.5 billion pounds over a 42 year period. |
| December 16, 1920 |
Finnish Admission to the League |
The League of Nations admitted Finland as a member state in the organization. |
| December 16, 1920 |
Bulgarian Admission to the League |
The League of Nations admitted Bulgaria as a member state in the organization. |
| December 16, 1920 |
Costa Rican Admission to the League |
The League of Nations admitted Costa Rica as a member state in the organization. |
| December 16, 1920 |
Luxembourg Admission to the League |
The League of Nations admitted Luxembourg as a member state in the organization. |
| December 17, 1920 |
Albanian Admission to the League |
The League of Nations admitted Albania as a member state in the organization. |
| December 17, 1920 |
Pacific Islands Mandates to Japan |
The League of Nations gave the former German islands in the Pacific north of the equator (the Caroline, Ladrone, Marianas, and Marshall Islands) to Japan. |
| December 17, 1920 |
League Confirmation of Pacific Mandates |
The League of Nations confirmed the establishment of mandates for Australia (German New Guinea), New Zealand (German Samoa), and a British condominium (Britain, Australia, and New Zealand) for Nauru. |
| December 19, 1920 |
Restoration of King Constantine of Greece |
King Constantine reclaimed his throne and announced that he would continue the war against the Turkey. In response, the Allies withdrew all support from Greece. |
| December 23, 1920 |
Government of Ireland Act |
To end the civil war in Ireland, the British parliament passed the Government of Ireland Act. The act established two separate parliaments, one in Dublin, for southern Ireland, and the other in Belfast, for northern Ireland, although both northern and southern Ireland continued to send MP's to Westminster. The act also set up the Council for Ireland, which again represented the two parts of the island, in an effort to promote cooperative action on common affairs. |
| December 23, 1920 |
Anglo-French Agreement on Syria and Palestine |
The British and French governments defined the borders between Syria, Palestine, and Iraq in a treaty. |
| December 27, 1920 |
Italian Bombardment of Fiume |
The Italian navy bombarded Fiume in response to Gabriele D'Annunzio's declaration of war. The attack forced D'Annunzio to evacuate the free state, but political disorders between autonomists and the nationalists continued. |
