This Timeline of events preceding World War II covers the events of the interwar period (1918-1939) after World War I that affected or led to World War II.
Germany and the Allied powers sign the Treaty of Versailles after six months of negotiations. The German armed forces are limited in size to 100,000 personnel and Germany is ordered to pay large reparations for war damages. The United States signed the treaty but did not ratify it, later making a separate peace treaty with Germany.
September 10
German Austria signs the Treaty of Saint-Germain. The peace treaty with the Allies regulates the borders of Austria, forbids union with Germany and German Austria has to change its name to Austria. The United States did not ratify the treaty and later makes a separate peace treaty with Austria.
November 27
Bulgaria signs the Treaty of Neuilly-sur-Seine. The peace treaty with the Allies regulates the borders of Bulgaria, the Bulgarian army is reduced to 20,000 men and Bulgaria is ordered to pay war reparations.
1920
January 10
Creation of the Free City of Danzig which was neither approved by Germany nor Poland.
January 21
The Paris Peace Conference comes to an end with the inaugural General Assembly of the League of Nations. Although one of the victors of World War I, the United States never joins the League.
March
The failed Kapp Putsch takes place against the German government. The German military remains passive and the putsch is defeated by a general strike.
The German Ruhr Uprising, spurred by the general strike against the Kapp Putsch, is crushed by the German military
June 4
Hungary signs the Treaty of Trianon with the Allied powers. The treaty regulated the status of an independent Hungarian state and defined its borders. The United States did not ratify the treaty and later makes a separate peace treaty with Hungary.
August 10
Turkey signs the Treaty of Sèvres with the Allied powers (except the US never declared war on Turkey). The treaty partitions the Ottoman Empire and the Turkish armed forces are reduced in size. Greece did not accept the borders as drawn up in the treaty and did not sign it. The Treaty of Sèvres was annulled in the course of the Turkish War of Independence and the parties signed and ratified the superseding Treaty of Lausanne in 1923.
The U.S.–German Peace Treaty and the U.S.–Austrian Peace Treaty are signed, marking the formal end of the state of war between the two states and the United States instead of the Treaty of Versailles and the Treaty of Saint-Germain that were not ratified by the United States.
August 29
The U.S.–Hungarian Peace Treaty is signed, marking the formal end of the state of war between the two states instead of the Treaty of Trianon that was not ratified by the United States.
1922
February 6
The Washington Naval Conference ends with the signing of the Washington Naval Treaty by the United Kingdom, the United States, Japan, France, and Italy. The signing parties agree to limit the size of their naval forces.
April 16
Germany and the Soviet Union sign the Treaty of Rapallo, re-establishing diplomatic relations, renouncing financial claims on each other and pledge future cooperation.
France and Belgium occupy the Ruhr in an effort to compel Germany to step up its payments of war reparations.
July 24
The Treaty of Lausanne, settling the boundaries of modern Turkey, is signed in Switzerland by Turkey and the Entente powers. It marks the end of the Turkish War of Independence and replaces the earlier Treaty of Sèvres.
August 31
The Corfu incident: Italy bombards and occupies the Greek island of Corfu seeking to pressure Greece to pay reparations for the murder of an Italian general in Greece.
September 27
The Corfu incident ends; Italian troops withdraw after the Conference of Ambassadors rules in favor of Italian demands of reparations from Greece.
October 29
Turkey officially becomes a Republic following the dissolution of the Ottoman Empire.
November 8
The Beer Hall Putsch takes place, in which Adolf Hitler unsuccessfully leads the Nazis in an attempt to overthrow the German government. It is crushed by police the next day.
1924
January 21
Leader of the Soviet Union Vladimir Lenin dies, and Joseph Stalin begins purging rivals to clear the way for his leadership.
Adolf Hitler is sentenced to 5 years in jail for his participation in the Beer Hall Putsch (he serves only 8 months).
April 6
Fascists win elections in Italy with a 2/3 majority.
June 10
Italian Fascists kidnap and kill socialist leader Giacomo Matteotti in Rome.
August 16
The Dawes Plan is accepted. It ends the Allied occupation of the Ruhr and sets a staggered payment plan for Germany's payment of war reparations.
August 18
France begins withdrawing its troops from the Ruhr in Germany.
1925
July 18
Adolf Hitler's autobiographical manifesto Mein Kampf is published.
December 1
The Locarno Treaties are signed in London (they are ratified 14 September 1926). The treaties settle the borders of western Europe and normalize relations between Germany and the Allied powers of western Europe.
Litvinov's Pact is signed in Moscow by the Soviet Union, Poland, Estonia, Romania and Latvia. The Pact outlaws aggressive warfare along the lines of the Kellog-Briand Pact.
February 11
Italy and the Holy See sign the Lateran Treaty, normalizing relations between the Vatican and Italy.
March 28
Japan withdraws troops from China, ending the Jinan Incident.
The Young Plan, which sets the total World War I reparations owed by Germany at US$26,350,000,000 to be paid over a period of 58½ years, is finalized. It replaces the earlier Dawes Plan.
The United Kingdom, United States, France, Italy and Japan sign the London Naval Treaty regulating submarine warfare and limiting naval shipbuilding.
June 30
France withdraws its remaining troops from the Rhineland ending the occupation of the Rhineland.
1931
September 18
Mukden Incident: the Japanese stage a false flag bombing against a Japanese-owned railroad in the Chinese region of Manchuria, blaming Chinese dissidents for the attack.
January 28 Incident: using a flare-up of anti-Japanese violence as a pretext, the Japanese attack Shanghai, China. Fighting ends on March 6, and on May 5 a ceasefire agreement is signed wherein Shanghai is made a demilitarized zone.
February 27
Fighting between China and Japan in Manchuria ends with Japan in control of Manchuria.
March 1
Japan creates the puppet state Manchukuo out of occupied Manchuria.
Japan leaves the League of Nations over the League of Nations' Lytton Report that found that Manchuria belongs to China and that Manchukuo was not a truly independent state.
The Tanggu Truce is signed between China and Japan, setting the ceasefire conditions between the two states after the Japanese occupation of Manchuria. China accedes to all Japanese demands, creating a large demilitarized zone inside Chinese territory.
June 21
All non-Nazi parties are banned in Germany.
July 14
The Nazi party becomes the official party of Germany.
August 25
Haavara Agreement: The agreement was designed to help facilitate the emigration of German Jews to Palestine.
All German police forces come under the command of Heinrich Himmler.
June 30
Night of the Long Knives in Germany. Potential rivals to Hitler within the Nazi Party, including SA leader Ernst Röhm, and prominent anti-Nazi conservatives are killed by the SS and the Gestapo.
July 20
The SS becomes an organization independent of the Nazi Party, reporting directly to Adolf Hitler.[2]
The League of Nations approves the results of the Saar plebiscite, which allows Saar to be incorporated into German borders.[3]
June 18
The Anglo-German Naval Agreement is signed by Germany and the United Kingdom. The agreement allows Germany to build a fleet that's 35% the tonnage of the British fleet. In this way, the British hope to limit German naval re-armament.
August 31
The Neutrality Act of 1935 is passed in the United States imposing a general embargo on trading in arms and war materials with all parties in a war and it also declared that American citizens travelling on ships of warring nations travelled at their own risk.
September 15
The Reichstag passes the Nuremberg Laws, introducing antisemitism in German legislation
In 1936, Adolf Hitler demanded to have a private meeting with Arnold J. Toynbee who was visiting Berlin the same year to address the Nazi Law Society, and Toynbee accepted.[4] In the meeting, Hitler emphasized his limited expansionist aim of building a greater German nation, and his desire for British understanding and cooperation. Toynbee was convinced of Hitler's sincerity, and endorsed Hitler's message in a confidential memorandum for the British prime minister and foreign secretary.[5]
The Second London Naval Treaty is signed by the United Kingdom, United States, and France. Italy and Japan each declined to sign this treaty.
May 5
Italian troops march into the Ethiopian capital, Addis Addeba, marking the end of the Second Italo–Abyssinian War.
June 3
Luftwaffe Chief of Staff General Walther Wever loses his life in an air crash, ending any hope for the Luftwaffe to ever have a strategic bombing force similar to the Allies.
Hermann Göring is made head of the German Four Year Plan, an effort to make Germany self-sufficient and increase armaments.
October
The Great Purge commences in the Soviet Union with widespread repression of suspected opponents of the regime. The purge leads to the imprisonment and death of many military officers, weakening the Soviet Armed Forces ahead of World War II.
Suiyuan Campaign begins as Japanese-backed Mongolian troops attack the Chinese garrison at Hongort.
November 15
The aerial German Condor Legion goes into action for the first time in the Spanish Civil War in support of the Nationalist side.
November 25
The Anti-Comintern Pact is signed by Japan and Germany. The signing parties agree to go to war with the Soviet Union if one of the signatories is attacked by the Soviet Union.
December 1
Hitler makes it mandatory for all males between the ages 10-18 to join the Hitler Youth.
December 12
The two sides in the Chinese Civil War temporarily suspend hostilities to fight the Japanese.
December 23
The first 3,000 men of the Italian expeditionary force (later named Corpo Truppe Volontarie) lands in Cadiz in support of the Nationalist side in the Spanish Civil War.
Soviet Union wins the Battle of Lake Khasan against Japan.
September 27
U.S. President Roosevelt sends letter to German Führer Adolf Hitler seeking peace.[8]
September 30
The Munich Agreement is signed by Germany, France, the United Kingdom, and Italy. The agreement allows Germany to annex the Czechoslovak Sudetenland area in exchange for peace in an attempt to appease Hitler.
The Kristallnachtpogrom begins in Germany; many Jewish shops and synagogues are smashed, looted, burned, and destroyed throughout the country.[10]
1939
January 25
A uranium atom is split for the first time at Columbia University in the United States.[11]
January 27
Adolf Hitler orders Plan Z, a 5-year naval expansion programme intended to provide for a huge German fleet capable of defeating the Royal Navy by 1944. The Kriegsmarine is given the first priority on the allotment of German economic resources. This is the first and only time the Kriegsmarine is given the first priority in the history of the Third Reich.
Germany occupies the Czech part in violation of the Munich Agreement. The Czechs do not attempt to put up any organized resistance having lost their main defensive line with the annexation of the Sudetenland.
Germany establishes the Protectorate of Bohemia and Moravia. The protectorate includes those portions of Czechoslovakia not incorporated into Germany, Poland, Hungary, or the new Slovak Republic.
The United Kingdom and France offer a guarantee of Polish independence.
April 1
The Spanish Civil War ends in Nationalist victory. Spain becomes a dictatorship with Francisco Franco as the head of the new government.
April 3
Adolf Hitler orders the German military to start planning for Fall Weiss, the codename for the attack on Poland, planned to be launched on August 25, 1939.
April 7–12
Italy invades Albania with little in the way of military resistance. Albania is later made part of Italy through a personal union of the Italian and Albanian crown.
April 14
U.S. President Roosevelt sends letter to German Chancellor Hitler seeking peace.[12]
April 18
The Soviet Union proposes a tripartite alliance with the United Kingdom and France. It is rejected.[13]
Soviet–Japanese border conflicts: The Battle of Khalkhin Gol begins with Japan and Manchukuo against the Soviet Union and Mongolia. The battle ends in Soviet victory on September 16, influencing the Japanese to not seek further conflict with the Soviets, but to turn towards the Pacific holdings of the Euro-American powers instead.
May 17
Sweden, Norway, and Finland reject Germany's offer of non-aggression pacts.
May 22
The Pact of Steel, known formally as the "Pact of Friendship and Alliance between Germany and Italy", is signed by Fascist Italy and Nazi Germany. The Pact declares further cooperation between the two powers, but in a secret supplement the Pact is detailed as a military alliance.
June 14
The Tientsin Incident occurs, in which the Japanese blockade the British concession in the North China Treaty Port of Tientsin.
July 10
Prime Minister Neville Chamberlain reaffirms support for Poland and makes it clear that Britain did not view Free City of Danzig as being an internal German-Polish affair and would intervene on behalf of Poland if hostilities broke out between the two countries.
In response to a message from Mussolini that Italy will not honor the Pact of Steel if Germany attacks Poland, Hitler delays the launch of the invasion by five days to provide more time to secure British and French neutrality.
^Carley, Michael Jabara (1993). "End of the 'Low, Dishonest Decade': Failure of the Anglo–Franco–Soviet Alliance in 1939". Europe–Asia Studies. 45 (2): 303–341. doi:10.1080/09668139308412091.