Timeline of events preceding World War II

1918

October 29

Start of the German Revolution.

November 11

The Armistice with Germany marks the end of World War I. German troops evacuate occupied territories and Allied troops subsequently move in and occupy the German Rhineland.

December 27

Start of the Greater Poland Uprising against German rule.

1919

January 4–15

The Spartacist uprising takes place and is crushed by the German government, marking the end of the German Revolution.

January 18

Opening of the Paris Peace Conference to negotiate peace treaties between the belligerents of World War I.

February

The Polish–Soviet War begins with border clashes between the two states.

March 2

Foundation of the Third International, or Comintern in Moscow. Comintern's stated aim is to create a global Soviet republic.

March 12

The Austrian Constituent National Assembly demands Austria's integration to Germany.

May 15

The Turkish War of Independence begins as Greek troops land in Smyrna.

June 28

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.

October

Żeligowski's Mutiny, a Polish force led by General Lucjan Żeligowski capture Vilnius, officially without support from the Polish state

1921

March

The Polish–Soviet War ends with the Peace of Riga.

August 25

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.

October

The Russian Civil War (ongoing since 7 November 1917) ends in Bolshevik victory with the defeat of the last White forces in Siberia.

October 29

Fascist leader Benito Mussolini is appointed prime minister of Italy by king Victor Emmanuel III after the March on Rome.

November 1

The Grand National Assembly of Turkey abolishes the Ottoman Sultanate.

1923

January 11

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.

February 1

The United Kingdom extends diplomatic recognition to the Soviet Union.

April 1

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.

1926

January 3

Theodoros Pangalos declares himself dictator of Greece.

January 31

British and Belgian troops leave Cologne, Germany.

April 4

Greek dictator Theodoros Pangalos is elected president.

April 24

The Treaty of Berlin is signed by Germany and the Soviet Union, which declares neutrality if either country is attacked within the next five years.

May 25

Ukrainian nationalist leader Symon Petliura is assassinated by Russian Jew Sholom Schwartzbard in Paris.

September 8

Germany joins the League of Nations.

December 25

Emperor Taishō dies and his son Hirohito becomes the Emperor of Japan.

1927

April 12

The Chinese Civil War begins between nationalists and communists.

May 20

Saudi Arabia and the United Kingdom sign the Treaty of Jeddah.

June 7

Peter Voikov, Soviet ambassador to Warsaw, is assassinated by a White movement activist.

November 12

Leon Trotsky is expelled from the Soviet Communist Party, leaving Joseph Stalin with undisputed control of the Soviet Union.

December 14

Iraq gains independence from the United Kingdom.

1928

May 3

The Jinan Incident begins, a limited armed conflict between the Republic of China and Japan.

June 4

Huanggutun Incident: Japanese agents assassinate the Chinese warlord Zhang Zuolin.

August 2

Italy and Ethiopia sign the Italo-Ethiopian Treaty, pledging cooperation and friendship.

August 27

The Kellogg-Briand Pact is signed in Paris by the major powers of the world. The treaty outlaws aggressive warfare.

October 1

The Soviet Union launches the First Five-Year Plan, an economic effort to increase industrialization.

1929

February 9

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.

April 3

Persia signs Litvinov's Pact.

June 7

The Lateran Treaty is ratified, making the Vatican City a sovereign state.

July 24

The Kellogg-Briand Pact goes into effect.

August 31

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.

October 29

The Great Depression begins with the Wall Street Crash.

1930

April 22

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.

September 19

Using the Mukden Incident as a pretext, the Japanese invade Manchuria.

1932

The Soviet famine of 1932–33 begins, caused in part by the collectivization of agriculture of the First Five-Year Plan.

January 7

The Stimson Doctrine is proclaimed by United States Secretary of State Henry L. Stimson in response to Japan invading Manchuria. The Doctrine holds that the United States government will not recognize border changes that are made by force.

January 28

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.

April 10

Paul von Hindenburg is reelected President of Germany, defeating Adolf Hitler in a run-off.

May 30

Chancellor of Germany Heinrich Brüning resigns. President von Hindenburg asks Franz von Papen to form a new government.

August 30

Hermann Göring is elected chairman of the German Senate.

November 21

Paul von Hindenburg begins talking to Adolf Hitler about forming a new government.

December 3

von Hindenburg names Kurt von Schleicher Chancellor of Germany.

1933

January 1

Defense of the Great Wall: Japan attacks the fortified eastern end of the Great Wall of China in Rehe Province in Inner Mongolia.

January 30

Nazi leader Adolf Hitler is appointed Chancellor of Germany by President Paul von Hindenburg.

February 27

Germany's parliament building the Reichstag is set on fire.

February 28

The Reichstag Fire Decree is passed, nullifying many German civil liberties.

March 4

Franklin Delano Roosevelt is inaugurated as President of the United States.

March 20

Germany's first concentration camp, Dachau, is completed.

March 23

The Reichstag passes the Enabling Act, making Adolf Hitler dictator of Germany.

March 24

Anti-Nazi boycott of 1933

March 27

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.

April 1

Germans are told to boycott Jewish shops and businesses in response to the Jewish boycott of German goods organized the previous month.

April 26

The Gestapo secret police is established in Germany.

May 2

Hitler outlaws trade unions.

May 31

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.

September 12

Leó Szilárd conceives the idea of the nuclear chain reaction.

October 17

Scientist Albert Einstein arrives in the United States and settles as a refugee from Germany.

October 19

Germany leaves the League of Nations.

November 24

Homeless, alcoholic, and unemployed sent to Nazi concentration camps.

1934

January 26

Germany and Poland sign the 10 year German-Polish Non-Aggression Pact.

February 12–16

The Austrian Civil War is fought, ending with Austrofascist victory.

March 20

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.

July 25

Austrian Nazis assassinate Engelbert Dollfuss during the failed July Putsch against the Austrian government.

August 2

Upon the death of President Paul von Hindenburg, Adolf Hitler makes himself Führer of Germany, becoming Head of State as well as Chancellor.

August 8

Members of the Wehrmacht begin swearing a personal oath of loyalty to Hitler instead of to the German constitution.

September

The Soviet Union joins the League of Nations.

December 5

The Abyssinia Crisis begins with the Walwal incident, an armed clash between Italian and Ethiopian troops on the border of Ethiopia.

December 29

Japan renounces the Washington Naval Treaty and the London Naval Treaty.

1935

January 7

The League of Nations approves the results of the Saar plebiscite, which allows Saar to be incorporated into German borders.

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

October 2

Italy invades Ethiopia, beginning the Second Italo–Abyssinian War.

1936

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. 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.

February 6

Germany hosts the 1936 Winter Olympics in Garmisch-Partenkirchen.

March 7

In violation of the Treaty of Versailles, Germany remilitarizes the Rhineland.

March 25

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.

July 17

The failed Spanish coup of July 1936 by Nationalist forces marks the beginning of the Spanish Civil War.

October 18

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.

August 1

Germany hosts the 1936 Summer Olympics in Berlin.

November 14

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.

1937

July 7

The Marco Polo Bridge Incident occurs, beginning the Second Sino-Japanese War.

October 5

U.S. president Franklin D. Roosevelt gives the Quarantine Speech outlining a move away from neutrality and towards "quarantining" all aggressors.

November 6

Italy joins the Anti-Comintern Pact.

December 8

Japan established the puppet state of Mengjiang in the Inner Mongolia region of the Republic of China.

December 11

Italy leaves the League of Nations.

December 12

The USS Panay incident occurs, where Japan attacked the American gunboat Panay while she was anchored in the Yangtze River.

December 13

Start of the Rape of Nanking following Japanese victory in the Battle of Nanking.

1938

January 26

The Allison incident occurs further straining relations between Japan and the United States.

March 6

Japanese troops reach the Yellow River in China.

March 13

Austria is incorporated by Germany.

July 6–16

Évian Conference: The United States and the United Kingdom refuse to accept any more Jewish refugees.

July 29

The Soviet–Japanese border conflicts begin with the Battle of Lake Khasan.

August

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.

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.

November 7

Exiled German Jew Herschel Grynszpan assassinates German consular aide Ernst vom Rath in Paris.

November 9

The Kristallnacht pogrom begins in Germany; many Jewish shops and synagogues are smashed, looted, burned, and destroyed throughout the country.

1939

January 25

A uranium atom is split for the first time at Columbia University in the United States.

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.

March 14

The pro-German Slovak Republic is created with Jozef Tiso as its first prime minister, provoking the dissolution of Czechoslovakia.

March 15

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.

March 20

German Foreign Minister Joachim von Ribbentrop delivers an oral ultimatum to Lithuania, demanding that it cede the Klaipėda Region (German name Memel) to Germany.

March 21

Adolf Hitler demands the return of the Free City of Danzig to Germany.

March 23

German–Romanian Treaty for the Development of Economic Relations between the Two Countries is signed.

March 31

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.

April 18

The Soviet Union proposes a tripartite alliance with the United Kingdom and France. It is rejected.

April 28

In a speech before the Reichstag, Adolf Hitler renounces the Anglo-German Naval Agreement and the German–Polish Non-Aggression Pact

May 11

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.

August 2

The Einstein-Szilárd letter is sent to Franklin D. Roosevelt. Written by Leó Szilárd and signed by Albert Einstein, it warned of the danger that Germany might develop atomic bombs. This letter prompted action by Roosevelt and eventually resulted in the Manhattan Project.

August 23

The Molotov-Ribbentrop Pact is signed between Nazi Germany and the Soviet Union, with secret provisions for the division of Eastern Europe - joint occupation of Poland and Soviet occupation of the Baltic States, Finland and Bessarabia. This protocol removes the threat of Soviet intervention during the German invasion of Poland.

August 25

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.

August 30

German ultimatum to Poland concerning the Polish Corridor and the Free City of Danzig

September 1

Without response to its ultimatum, Germany invades Poland, start of World War II.