Why did World War Two begin?

Part ofHistoryWorld War Two

What caused the start of World War Two?

On the morning of 1 September 1939, the first day of World War II, German soldiers remove the barrier at the German-Polish border on the road to Zoppot, Gdingen and Danzig and proceed to invade Poland.
Image caption,
Germany soldiers removing a Polish border barrier as they began their invasion of Poland on 1st September, 1939. This was the start of the Second World War.

The harsh treatment of Germany after the First World War was one of the main reasons that led to the outbreak of World War Two.

This made the German people feel weak and desperate, allowing Adolf Hitler and the Nazi Party (a fascist political party) to take control of Germany.

When Hitler’s forces invaded (when an armed force from one country enters another country to take control) Poland on 1st September, 1939, Britain and France had no choice but to declare war.

World War Two had now begun.

On the morning of 1 September 1939, the first day of World War II, German soldiers remove the barrier at the German-Polish border on the road to Zoppot, Gdingen and Danzig and proceed to invade Poland.
Image caption,
Germany soldiers removing a Polish border barrier as they began their invasion of Poland on 1st September, 1939. This was the start of the Second World War.
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Watch: Why did World War Two begin?

Discover the causes of World War Two.

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Important words

Important words on why World War Two began.

KeywordDefinition
AppeasementThe giving in to demands to avoid a conflict.
ArmisticeAn agreement between countries to stop fighting.
BlitzkriegThe German word for lightning war describes the quick and powerful movement of military soldiers and vehicles.
FascismA way of thinking that considers a country or race to be more important than others. It often has a single leader, and tries to control people who disagree.
FuhrerThe German word for leader.
Great DepressionA time when the world faced difficult economic conditions.
InvadedWhen an armed force from one country enters another country to take control.
Nazi PartyFascist political party led by Adolf Hitler.
ReparationsMoney demanded for damages.
Treaty of VersaillesA peace agreement which held Germany responsible for World War One.
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How did the end of First World War cause problems for the world?

Crowds in London celebrating the signing of the Armistice at the end of the First World War, 29th November, 1918.
Image caption,
Crowds in London celebrating the signing of the Armistice at the end of the First World War, 29th November, 1918.

The First World War was fought between 1914 and 1918 and caused the deaths of millions of soldiers and civilians.

On 11th November 1918, the armistice (an agreement between countries to stop fighting) was signed bringing an end to the First World War.

In 1919, the Treaty of Versailles was signed in France, the peace treaty made Germany accept full responsibility for the losses during the First World War.

This meant Germany lost land, could not rebuild its army and had to pay large sums of money, called reparations, to the Allies.

Crowds in London celebrating the signing of the Armistice at the end of the First World War, 29th November, 1918.
Image caption,
Crowds in London celebrating the signing of the Armistice at the end of the First World War, 29th November, 1918.
Image caption,
German people protesting unemployment in Berlin, 1930.

Throughout the 1920s, the German people started to feel the pain of the Treaty of Versailles, many people lost their jobs, the money they used lost its value and the prices of everyday items increased.

Many German people started to become angry at their government for signing the Treaty of Versailles.

In 1929, the world suffered from the Great Depression, this was a time when the world’s economy struggled.

Image caption,
German people protesting unemployment in Berlin, 1930.
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Who were the Nazi Party and how did they gain power in Germany?

Chancellor Adolf Hitler Making A Speech Before The Reichstag Berlin 17th May 1933.
Image caption,
New Chancellor Adolf Hitler at the Reichstag in Berlin, 17th May, 1933.

The Nazi Party was a political party created after the First World War, its leader was Adolf Hitler.

He blamed the government of Germany, their signing of the Treaty of Versailles and other communities, such as Jewish people, for Germany’s problems.

He promised to make Germany strong again, to remove the restrictions of the Treaty of Versailles and to regain the land that they had lost.

In 1933, Hitler became the Chancellor of Germany.

As Chancellor, he started to arrest his opponents and pass new laws that allowed him to become the supreme leader, or Fuhrer, of Germany.

Chancellor Adolf Hitler Making A Speech Before The Reichstag Berlin 17th May 1933.
Image caption,
New Chancellor Adolf Hitler at the Reichstag in Berlin, 17th May, 1933.
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Why did Britain choose appeasement?

Prime Minister Neville Chamberlain holding the Munich Agreement.
Image caption,
British Prime Minister Neville Chamberlain holding the Munich Agreement which gave Germany back the Sudetenland, he hoped this appeasement would avoid a Second World War.

As Fuhrer, Adolf Hitler immediately began to break the rules of the Treaty of Versailles, he started to rebuild Germany’s army and sign agreements with other countries like Italy and Japan.

In 1938, Germany invaded and conquered Austria which worried many leaders in Europe.

Britain and France were desperate to avoid another world war, so they allowed Germany to keep the lands it had taken, they also allowed Germany to invade the Sudetenland in Czechoslovakia.

This decision was called appeasement (the giving in to demands to avoid a conflict).

Hitler signed an agreement to promise not to expand Nazi Germany, this was called the Munich Agreement.

On 1st September, 1939, Hitler broke the Munich Agreement and launched an invasion of Poland, they used a tactic called blitzkrieg (the quick movement of military soldiers and vehicles) and it overwhelmed the Polish forces.

The policy of appeasement failed, Britain and France had no choice but to declare war on Germany two days later on 3rd September, 1939.

Prime Minister Neville Chamberlain holding the Munich Agreement.
Image caption,
British Prime Minister Neville Chamberlain holding the Munich Agreement which gave Germany back the Sudetenland, he hoped this appeasement would avoid a Second World War.
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When and why did the USA become involved in World War Two?

An explosion at the Naval Air Station, Ford Island, Pearl Harbor.
Image caption,
On 7th December, 1941, the Japanese bombed the US naval base at Pearl Harbor bringing the United States into the war.

When World War Two began, the United States of America (USA) did not want to get involved in another European war.

After Japan signed an agreement with Nazi Germany, the relationship between the USA and Japan became much worse.

On 7th December, 1941, Japan launched a surprise attack on the US Naval base at Pearl Harbor, in Hawaii killing 2,403 soldiers and civilians and destroying warships.

The day after the attack, the American President, Franklin D Roosevelt, declared war on Japan. Germany and Italy then quickly declared war on the USA on 11th December, 1941.

The USA had now joined World War Two.

An explosion at the Naval Air Station, Ford Island, Pearl Harbor.
Image caption,
On 7th December, 1941, the Japanese bombed the US naval base at Pearl Harbor bringing the United States into the war.
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Think like a historian

A thought bubble saying 'Thinking points'.

Have a look at the thinking points below and think about your answer to each question. You could even write them down on a piece of paper or discuss them with somebody else if you want to.

  • What do you think was the most important consequence of the German people feeling unhappy, defeated and desperate after the Treaty of Versailles was signed?

  • The policy of Appeasement failed to prevent the outbreak of World War Two. Why do you think this failure was a significant event which led to the outbreak of World War Two?

  • Adolf Hitler blamed the German government and different groups of people for Germany’s problems. What do you think this tells historians about how Hitler succeeded in becoming the supreme leader of Germany?

A thought bubble saying 'Thinking points'.

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Activities

Activity: Quiz

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Grown-ups corner

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