FIELD NOTES / SECOND WORLD WAR

Facts of World War 2: 20 Key Facts About 1939–1945

British tanks at El Alamein in 1942 during the Second World War

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The Second World War lasted from 1939 to 1945 and became the deadliest conflict in human history. It was fought across Europe, Africa, Asia, the Atlantic and Pacific, transformed civilian life on a vast scale and ended with a fundamentally different international order.

These 20 World War 2 facts are a starting point. Each section links into the deeper Gallus guides where the ground, chronology and people can be followed properly.

20 key facts of World War 2

  1. The war in Europe began with Germany’s invasion of Poland on 1 September 1939. Britain and France declared war on Germany on 3 September.
  2. The conflict was genuinely global. Fighting extended across Europe, North and East Africa, the Middle East, the Atlantic, Asia and the Pacific.
  3. Poland was invaded from both west and east in September 1939. Germany attacked from the west; the Soviet Union invaded eastern Poland later that month under the geopolitical settlement created by the Nazi-Soviet Pact.
  4. France fell in 1940. German forces broke through the Low Countries and France in a rapid campaign that forced the British Expeditionary Force and other Allied troops to evacuate from Dunkirk.
  5. Britain then faced the Battle of Britain. During the summer and autumn of 1940 the RAF resisted the Luftwaffe’s attempt to gain the air superiority needed for a possible invasion.
  6. The Blitz brought the war directly to British civilians. London and many other British cities suffered sustained German bombing.
  7. Germany invaded the Soviet Union on 22 June 1941. Operation Barbarossa opened the enormous Eastern Front, which became central to Nazi Germany’s eventual defeat.
  8. Japan attacked Pearl Harbor on 7 December 1941. The attack brought the United States directly into the war.
  9. Britain fought major campaigns in North Africa. The battles around El Alamein in 1942 became a turning point in the struggle against Axis forces in Egypt and Libya.
  10. Stalingrad became one of the war’s decisive battles. The German Sixth Army surrendered in early 1943 after months of catastrophic fighting.
  11. The Holocaust was a systematic, state-sponsored genocide. Nazi Germany and its collaborators murdered six million Jews, alongside the persecution and mass murder of millions of other victims.
  12. The Allies invaded Sicily and Italy in 1943. Mussolini was removed from power, but fighting in Italy continued against German forces until 1945.
  13. D-Day took place on 6 June 1944. Allied troops landed on five main Normandy beaches — Utah, Omaha, Gold, Juno and Sword — while airborne forces landed inland.
  14. Operation Overlord was larger than the landings themselves. D-Day opened the Allied campaign in Normandy and the liberation of Western Europe.
  15. Paris was liberated in August 1944. Allied forces continued east while Germany fought to delay the advance.
  16. Germany made one final major western counter-offensive in the Ardennes. The Battle of the Bulge began in December 1944.
  17. Hitler died on 30 April 1945 as Soviet forces fought through Berlin.
  18. VE Day was 8 May 1945. It marked victory in Europe following Germany’s unconditional surrender.
  19. The war continued in Asia after VE Day. The United States dropped atomic bombs on Hiroshima and Nagasaki in August; the Soviet Union also entered the war against Japan.
  20. The Second World War formally ended with Japan’s surrender on 2 September 1945. The National Army Museum describes a death toll of more than 65 million people, with civilians forming the majority.

Why World War 2 cannot be reduced to Europe

British memory understandably focuses heavily on Dunkirk, the Battle of Britain, North Africa, D-Day and VE Day. But the war also depended on enormous campaigns in the Soviet Union, China, South-East Asia and the Pacific, as well as the global maritime struggle that connected them.

A useful overview should therefore treat 1939–45 as one global conflict rather than a sequence of isolated British set pieces.

D-Day: the best-known British and Allied entry point

For many readers, D-Day is the route into the wider war. Gallus has a complete chain from the planning and deception through the five beaches and airborne operations.

The human cost

Any ‘facts’ page risks turning a war into numbers. The scale matters, but so do the individuals inside it. The Holocaust alone involved the murder of six million Jews by Nazi Germany and its allies and collaborators, while many millions of other civilians and service personnel died across the wider conflict.

The National Archives also records the war at a much smaller scale: unit war diaries, casualty lists, service records, government papers and the 1939 Register. Those records are where a family story can be connected back to the larger war.

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Explore the connected history

Gallus designs are built from the same campaigns, dates and places covered in the archive. Explore the World War 2 collection →

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