What caused the start of World War Two?

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.

Watch: Why did World War Two begin?
Discover the causes of World War Two.
“…this country is at war with Germany.”
So, we're at war again.
None of us wanted this.
But the warning signs have been building for years.
After the last war, Germany was forced to sign the Treaty of Versailles.
This was a peace agreement, but it was extremely tough on Germany.
It made them pay huge sums of money to other countries.
The military had to be really small. They lost land.
It left many German people angry and humiliated.
Along with other difficulties, it left them struggling to survive.
Then along comes Adolf Hitler and the Nazi Party.
He promised strength, pride, jobs, and the Germans, many desperate for change, put him in power.
Once there, he started expanding the military.
His plan was to control more land by taking it from other countries.
“Living space,” he called it.
And Britain and France just looked the other way. Appeasement.
Anything to avoid another war.
But this just made Hitler more confident.
And then at Munich, Hitler promised he would take no more land.
Britain's Prime Minister, Neville Chamberlain, even called it “peace for our time.”
But less than a year later, German troops marched into Poland to invade.
At that point, Britain and France declared war on Germany.
All the while, Italy, led by Mussolini, has been sending its armies to take over land in Africa and the Mediterranean, trying to build an empire of its own.
And far to the east, Japan has invaded China and has been expanding across Asia for years.
And now…
…we have to face what is to come.
Important words
Important words on why World War Two began.
| Keyword | Definition |
|---|---|
| Appeasement | The giving in to demands to avoid a conflict. |
| Armistice | An agreement between countries to stop fighting. |
| Blitzkrieg | The German word for lightning war describes the quick and powerful movement of military soldiers and vehicles. |
| Fascism | A 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. |
| Fuhrer | The German word for leader. |
| Great Depression | A time when the world faced difficult economic conditions. |
| Invaded | When an armed force from one country enters another country to take control. |
| Nazi Party | Fascist political party led by Adolf Hitler. |
| Reparations | Money demanded for damages. |
| Treaty of Versailles | A peace agreement which held Germany responsible for World War One. |
How did the end of First World War cause problems for the world?

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.


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.

Who were the Nazi Party and how did they gain power in Germany?

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.

Why did Britain choose appeasement?

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.

When and why did the USA become involved in World War Two?

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.

Think like a historian

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?

Did you think that the most important consequence was the rise of Adolf Hitler? The Treaty of Versailles created a chance for the Nazi Party to gain power by promising to fix Germany’s problems and make it strong again. Maybe you thought it was the economic impact of the Treaty of Versailles on Germany in the 1920’s? This made Germany and its government weak and unable to oppose the promises Adolf Hitler and the Nazi Party made.
Perhaps you thought it was a significant event because it showed that Britain and France were unwilling to commit to stopping Adolf Hitler from breaking the rules of the Treaty of Versailles. This encouraged Hitler to continue his invasion of other countries. After Appeasement failed, Britain and France had no choice but to declare war on Germany, despite wanting to avoid another world war.
Hitler used people’s feelings of being desperate and unhappy so they would listen to his promises to fix Germany and make it strong again. Maybe you thought about how he needed someone to blame for the country’s desperation and problems. He could then offer a solution to fix the problems created by the Treaty of Versailles.
Activities
Activity: Quiz
Grown-ups corner
Are you a parent, carer or teacher?
Take a look at some of the links below on KS2 History which are packed full of knowledge, videos, quizzes and activities.
KS2 History: Britain declares war on Germany
BBC Bitesize for Teachers

KS2 History: Geography of World War Two
BBC Bitesize for Teachers

Primary History KS2: WW2 Clips. The declaration of war
BBC Bitesize for Teachers

Horrible Histories: Raid and Trade game! gameHorrible Histories: Raid and Trade game!
Play Horrible Histories: Raid and Trade KS2 History

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