Causes of war and the war years

Newspaper headline illustration "Great Britain declares war"

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On 4 August 1914, Britain declared war on Germany. People in Britain opened their newspapers the next morning and found out war had begun.

It became known as The Great War because it affected people all over the world and was the biggest war anyone had ever known. The war was fought between two powerful groups.

Triple Alliance and Triple Entente sides

Map of  Triple Alliance and Triple Entente

The opposing sides were:

  • The Triple Alliance - made up of Germany, Austria-Hungary and Italy
  • The Triple Entente - made up of Great Britain, France and Russia

Long before the war began, the countries in these groups had made arrangements to work together and help one another if there was a war. So when war did break out in 1914, parts of Europe was already divided into two sides.

Each of the countries involved got their troops ready to fight. Troops were groups that fought together and included both the army (people who fight on land) and the navy (people who fight on the seas). Although part of the Triple Alliance, Italy declared neutrality at the outbreak of war. Italy then entered the war on the side of the Triple Entente in 1915.

The war saw lots of battles take place in different countries, especially France and Belgium. Later, many other countries also become involved, some on the side of the Triple Alliance and others of the side on the Triple Entente.

Navy crew in WW1 The crew of HMS Swift, a British high speed destroyer ship on deck during World War One

Teachers' notes

Teachers' notes and classroom ideas looking at causes of the war and the war years.

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