World War 2 & 20th-century Britain: the World Wars to today

Last reviewed 21 July 2026 · Reviewed by the BritainTest editorial team

For the test, the essentials are: the First World War ran from 1914 to 1918, World War 2 from 1939 to 1945 with Winston Churchill as wartime Prime Minister from 1940, and the NHS was founded in 1948. This guide covers those and the rest of the 20th century that shaped modern Britain. It follows on from the Industrial Revolution and the Empire, and it is part of our history study guide.

Key facts

The First World War (1914 to 1918)

Britain and its allies fought Germany and its allies in the First World War, from 1914 to 1918. The loss of life was huge, and it is remembered each year on Remembrance Day, 11 November, when people wear poppies. Soon after, most of Ireland became independent in 1922, while Northern Ireland remained part of the UK.

World War 2 (1939 to 1945)

Britain fought Nazi Germany in the Second World War (World War 2), from 1939 to 1945. Winston Churchill became Prime Minister in 1940 and led Britain for most of the war; his wartime speeches made him one of the most famous Britons in history. Key moments to know:

• The evacuation of troops from Dunkirk in 1940, when hundreds of small boats helped rescue over 300,000 soldiers.
• The Battle of Britain (summer 1940), when the RAF defended the country from German air attacks in the skies over Britain.
• The Blitz, the German bombing of London and other cities, including Coventry.
• D-Day, 6 June 1944, when Allied forces landed in Normandy and began the liberation of Europe.

The Nazis were responsible for the Holocaust, the murder of millions of Jewish people and others.

The welfare state and the NHS

After the war, the government of Clement Attlee built a welfare state to support people from cradle to grave, based on the ideas of William Beveridge. In 1948, the National Health Service (NHS) was founded, providing healthcare for everyone, free at the point of use.

A more diverse Britain

After 1945, people were invited to come and help rebuild the country and staff the new NHS, many from the Caribbean and South Asia. At the same time, the British Empire was gradually dismantled, and most former colonies became independent, with many joining the Commonwealth. Together these changes made modern Britain a diverse, multicultural society.

Modern Britain

The later 20th century brought big social change: the "swinging sixties" saw new freedoms, British pop music conquer the world, and laws improving women's rights, such as the Equal Pay Act. In 1979, Margaret Thatcher became the UK's first woman Prime Minister. In Northern Ireland, the violence of the Troubles largely ended with the Good Friday Agreement in 1998. Devolution then gave Scotland and Wales their own governments after referendums in 1997, and Northern Ireland its Assembly under the 1998 agreement, all sitting from 1999. The UK joined the European Economic Community in 1973, and later left the European Union in 2020.

What to remember for the test

• 1914 to 1918: the First World War.
• 1939 to 1945: World War 2; Winston Churchill became Prime Minister in 1940 and led Britain.
• Dunkirk and the Battle of Britain in 1940; D-Day on 6 June 1944.
• 1948: the NHS is founded, under Attlee's post-war government.
• Remembrance Day is 11 November.
• 1998: the Good Friday Agreement; devolved governments sit from 1999.
• Post-war Britain built the welfare state and became more diverse.

For these dates alongside the others, see the UK history timeline.

Practise this topic

Test yourself on modern British history in the real format, then reread anything you miss. The last history guide looks at Britain's great inventions and inventors.