World War II

Table of Contents

Introduction & Top Questions
Axis initiative and Allied reaction
- The outbreak of war
- Forces and resources of the European combatants, 1939
- Technology of war, 1918–39
- The war in Europe, 1939–41
  - The campaign in Poland, 1939
  - The Baltic states and the Russo-Finnish War, 1939–40
  - The war in the west, September 1939–June 1940
    - The invasion of Norway
    - The invasion of the Low Countries and France
    - The evacuation from Dunkirk
    - Italy’s entry into the war and the French Armistice
  - The Battle of Britain
  - Central Europe and the Balkans, 1940–41
- Other fronts, 1940–41
  - Egypt and Cyrenaica, 1940–summer 1941
  - East Africa
  - Iraq and Syria, 1940–41
  - The beginning of lend-lease
  - The Atlantic and the Mediterranean, 1940–41
  - German strategy, 1939–42
- Invasion of the Soviet Union, 1941
- The war in the Pacific, 1938–41
  - The war in China, 1937–41
  - Japanese policy, 1939–41
  - Pearl Harbor and the Japanese expansion, to July 1942
  - The fall of Singapore
  - The Chinese front and Burma, 1941–42
- Developments from autumn 1941 to spring 1942
  - Allied strategy and controversies, 1940–42
  - Libya and Egypt, autumn 1941–summer 1942
  - The Germans’ summer offensive in southern Russia, 1942
The Allies’ first decisive successes
- The Solomons, Papua, Madagascar, the Aleutians, and Burma, July 1942–May 1943
- Burma, autumn 1942–summer 1943
- Montgomery’s Battle of el-Alamein and Rommel’s retreat, 1942–43
- Stalingrad and the German retreat, summer 1942–February 1943
- The invasion of northwest Africa, November–December 1942
- Tunisia, November 1942–May 1943
- The Atlantic, the Mediterranean, and the North Sea, 1942–45
- Air warfare, 1942–43
- German-occupied Europe
- Casablanca and Trident, January–May 1943
- The Eastern Front, February–September 1943
- The Southwest and South Pacific, June–October 1943
The Allied landings in Europe and the defeat of the Axis powers
- Developments from autumn 1943 to summer 1944
  - Sicily and the fall of Mussolini, July–August 1943
  - The Quadrant Conference (Quebec I)
  - The Allies’ invasion of Italy and the Italian volte-face, 1943
  - The western Allies and Stalin: Cairo and Tehrān, 1943
  - German strategy, from 1943
  - The Eastern Front, October 1943–April 1944
  - The war in the Pacific, October 1943–August 1944
    - The encirclement of Rabaul
    - Western New Guinea
    - The central Pacific
  - The Burmese frontier and China, November 1943–summer 1944
  - The Italian front, 1944
- Developments from summer 1944 to autumn 1945
  - The Allied invasions of western Europe, June–November 1944
  - The Eastern Front, June–December 1944
  - Air warfare, 1944
  - Allied policy and strategy: Octagon (Quebec II) and Moscow, 1944
  - The Philippines and Borneo, from September 1944
  - Burma and China, October 1944–May 1945
  - The German offensive in the west, winter 1944–45
  - The Soviet advance to the Oder, January–February 1945
  - Yalta
  - The German collapse, spring 1945
  - Potsdam
  - The end of the Japanese war, February–September 1945
    - Iwo Jima and the bombing of Tokyo
    - Okinawa
    - Hiroshima and Nagasaki
    - The Japanese surrender
- Costs of the war
  - Killed, wounded, prisoners, or missing
  - Human and material cost
    - Europe
    - The Far East

References & Edit History Quick Facts & Related Topics

Images, Videos & Interactives

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World War II: Facts & Related Content

Written and fact-checked by The Information Architects of Encyclopaedia Britannica

Facts

Also Known As	WWII • Second World War
Date	September 3, 1939 - September 2, 1945
Participants	Canada • China • France • Germany • India • Italy • Japan • Soviet Union • United Kingdom • United States

Did You Know?

About 70 million total soldiers fought on behalf of the Allied or Axis countries.
Some scholars argue that the "start" of WWII was in 1937 when Japan invaded China instead of when Germany invaded Poland.
Switzerland, Spain, Portugal and Sweden all declared themselves neutral during WWII.

Photos and Videos

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Topics

panzer Colossus blitzkrieg Sherman tank Lancaster P-51 C-47 Bf 109 B-17 Spitfire

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Timeline

Samuel Bak: Smoke

Holocaust

1933 - 1945

Invasion of Poland

Invasion of Poland

September 1, 1939 - October 5, 1939

Learn how the Third Reich utilized U-boats in the Battle of the Atlantic to destroy Allied supply convoys

Battle of the Atlantic

September 3, 1939 - May 8, 1945

Dunkirk evacuation

Dunkirk evacuation

May 26, 1940 - June 4, 1940

North Africa campaigns of World War II

North Africa campaigns

June 1940 - May 13, 1943

Battle of Britain

July 1940 - September 1940

Vichy: Battle of France

Vichy France

July 1940 - September 1944

German bombing of London during the Blitz

the Blitz

September 7, 1940 - May 11, 1941

aftermath of the Battle of Crete

Battle of Crete

May 20, 1941 - June 1, 1941

German soldiers during Operation Barbarossa

Operation Barbarossa

June 22, 1941

German troops at the Battle of Moscow, 1941–1942

Battle of Moscow

September 30, 1941 - January 7, 1942

Pearl Harbor attack

Pearl Harbor attack

December 7, 1941

Battle of Wake Island

December 8, 1941 - December 23, 1941

U.S. troops advancing on Tarawa, Gilbert Islands, in 1943

Pacific War

December 8, 1941 - September 2, 1945

Bataan Death March

Bataan Death March

April 9, 1942

eastern New Guinea, from the 10th edition of Encyclopædia Britannica, c. 1902

Kokoda Track Campaign

July 1942 - January 1943

Battle of Stalingrad

Battle of Stalingrad

August 22, 1942 - February 2, 1943

Warsaw Ghetto Uprising

Warsaw Ghetto Uprising

April 19, 1943 - May 16, 1943

Allied decoy tank

Operation Fortitude

1944

Normandy Invasion

Normandy Invasion

June 6, 1944 - July 9, 1944

U.S. Marines on Saipan, Mariana Islands, 1944

Battle of Saipan

June 15, 1944 - July 9, 1944

Operation Bagration

June 23, 1944 - August 19, 1944

Cowra, New South Wales, Australia

Cowra breakout

August 5, 1944

Operation Market Garden

September 17, 1944 - September 27, 1944

Battle of the Bulge

Battle of the Bulge

December 16, 1944 - January 16, 1945

Yalta Conference

Yalta Conference

February 4, 1945 - February 11, 1945

Battle of Iwo Jima

Battle of Iwo Jima

February 19, 1945 - March 26, 1945

Battle for Castle Itter

May 5, 1945

Atomic bombing of Hiroshima

atomic bombings of Hiroshima and Nagasaki

August 6, 1945 - August 9, 1945

Key People

Alessandro Pertini

president of Italy

Puller, Chesty

Chesty Puller

United States Marine Corps officer

Edward O'Hare

Edward O’Hare

American aviator and WWII hero

Winston Churchill

Winston Churchill

prime minister of United Kingdom

Adolf Hitler

Adolf Hitler

dictator of Germany

Franklin D. Roosevelt

Franklin D. Roosevelt

president of United States

Joseph Stalin

Joseph Stalin

premier of Soviet Union

Dwight D. Eisenhower

Dwight D. Eisenhower

president of United States

Benito Mussolini

Benito Mussolini

Italian dictator

Charles de Gaulle

Charles de Gaulle

president of France

Harry S. Truman

Harry S. Truman

president of United States

George S. Patton

George Patton

United States general

Josip Broz Tito

Josip Broz Tito

president of Yugoslavia

Alan Turing

Alan Turing

British mathematician and logician

Chiang Kai-shek

Chiang Kai-shek

Chinese statesman

Hermann Göring

Hermann Göring

German minister

George C. Marshall

George C. Marshall

United States general

Douglas MacArthur

Douglas MacArthur

United States general

Erwin Rommel

Erwin Rommel

German field marshal

Joseph Goebbels

Joseph Goebbels

German propagandist

Quiz

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