Explained In 5 Questions: World War II | Encyclopaedia Britannica

Summary

The video explains World War II through five questions: how it began, who fought, who led the sides, which events changed its course, and how it ended.

How did the war begin and expand?

War in Europe officially began on September 1, 1939, when Germany invaded Poland. Britain and France declared war on Germany two days later. The conflict widened when Germany invaded the Soviet Union in June 1941 and Japan attacked the U.S. naval base at Pearl Harbor on December 7, 1941. The attack brought the United States into the war and extended the conflict across the Pacific.

Who fought?

The main opposing coalitions were:

• Axis powers: Germany, Italy, and Japan.
• Allied powers: Great Britain, France, the Soviet Union, and the United States. China, already fighting Japan, is also sometimes counted among the Allies.

Many other nations were affected by the conflict.

Who led the major powers?

The Allies were led by Winston Churchill, Joseph Stalin, Charles de Gaulle, and Franklin D. Roosevelt. After Roosevelt died near the end of the war, Harry S. Truman became U.S. president.

The Axis leaders named are Adolf Hitler, Benito Mussolini, and Hideki Tojo. Tojo had succeeded Kuniaki Koiso as Japan’s prime minister.

Which battles turned the tide?

• Midway (1942): U.S. forces destroyed Japan’s first-line carrier force, marking a major shift in the Pacific. Along with the Battle of Guadalcanal, it ended Japan’s ability to wage an offensive war.
• Stalingrad (ending in February 1943): The Soviet Union defeated Germany at enormous human cost. Germany lost two armies and failed to take the city, marking a major reversal on the Eastern Front.

How did the war end?

Europe

The Allied invasion of Normandy on June 6, 1944—D-Day—opened a second front. Germany’s final offensive in the Ardennes in the winter of 1944–45 failed. Soviet forces advanced from the east while American and British forces moved through France from the west. Hitler died by suicide on April 30, 1945, and the war in Europe ended on May 8.

The Pacific

U.S. island-hopping and bombing campaigns weakened Japan. The atomic bombings of Hiroshima and Nagasaki in August 1945, together with the threat of Soviet invasion, helped bring about Japan’s surrender.

Speakers and sources featured

• Unidentified narrator
• Franklin D. Roosevelt: Archival speech excerpt about the attack on Pearl Harbor
• Douglas MacArthur: Archival excerpt inviting Japan’s representatives to sign the Instrument of Surrender