World War II

American  

noun

1. the war between the Axis and the Allies, beginning on September 1, 1939, with the German invasion of Poland and ending with the surrender of Germany on May 8, 1945, and of Japan on August 14, 1945. WWII

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World War II British  

noun

1. Also called: Second World War.  the war (1939–45) in which the Allies (principally Britain, the Soviet Union, and the US) defeated the Axis powers (principally Germany, Italy, and Japan). Britain and France declared war on Germany (Sept 3, 1939) as a result of the German invasion of Poland (Sept 1, 1939). Italy entered the war on June 10, 1940 shortly before the collapse of France (armistice signed June 22, 1940). On June 22, 1941 Germany attacked the Soviet Union and on Dec 7, 1941 the Japanese attacked the US at Pearl Harbor. On Sept 8, 1943 Italy surrendered, the war in Europe ending on May 7, 1945 with the unconditional surrender of the Germans. The Japanese capitulated on Aug 14, 1945 as a direct result of the atomic bombs dropped by the Americans on Hiroshima and Nagasaki

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World War II Cultural  

1. A war fought from 1939 to 1945 between the Axis powers — Germany, Italy, and Japan — and the Allies, including France and Britain, and later the Soviet Union and the United States. The war began when the Germans, governed by the Nazi party, invaded Poland in September 1939 (see invasion of Poland). Germany then conquered France, using blitzkrieg tactics, and forced a desperate British withdrawal at Dunkirk. The Germans tried to wear down the British by heavy bombing, but the British withstood the attacks (see Battle of Britain). The Soviet Union signed a treaty with Adolf Hitler but entered the war on the side of the Allies after Germany invaded Russia in 1941. The United States was drawn into the war in 1941, when the Japanese suddenly attacked the American naval base at Pearl Harbor. Japan made extensive conquests in east Asia but was checked by American victories at the Battle of Midway Island and elsewhere. The German invasion of Russia was halted at the Battle of Stalingrad. Allied forces took much of Italy in 1943, forcing its surrender. Beginning with the invasion of Normandy in 1944 (see D-Day), the Allies liberated France from German occupation and pressed on in Europe, defeating the Germans in the Battle of the Bulge and elsewhere. Germany surrendered in May 1945 (see V-E Day). The war in the Pacific ended in September 1945 (see V-J Day), after the United States dropped atomic bombs (see also atomic bomb) on the Japanese cities of Hiroshima (see also Hiroshima) and Nagasaki. In the aftermath of World War II, more constructive and less punitive measures were applied to the defeated countries than after World War I (see Marshall Plan, Nuremberg trials, and United Nations).

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The political leaders of the war included Winston Churchill of Britain, Adolf Hitler of Germany, Benito Mussolini of Italy, Franklin D. Roosevelt of the United States, and Joseph Stalin of the Soviet Union. The military leaders included Charles De Gaulle of France; Bernard Montgomery of Britain; Hermann Goering and Erwin Rommel of Germany; Tito of Yugoslavia; and Omar Bradley, Dwight Eisenhower, William Halsey, Douglas MacArthur, Chester Nimitz, and George Patton of the United States.

Example Sentences

President Abraham Lincoln cycled through five commanding generals during the Civil War, and dozens of generals were retired or relieved of command during World War II.

From Salon • May 1, 2026

According to the Economic Policy Institute, in the immediate three decades after World War II, workers saw their hourly compensation in line with the country’s productivity growth.

From Los Angeles Times • May 1, 2026

Ukrainian President Volodymyr Zelensky on Thursday said Kyiv would seek details from Washington about a Kremlin offer for a ceasefire on May 9, when Russia holds large-scale World War II commemorations.

From Barron's • Apr. 30, 2026

The U.S. mobilized to fight World War II, then rapidly demobilized after it ended.

From The Wall Street Journal • Apr. 28, 2026

During World War II, the US government took 500,000 more acres for military use.

From "An Indigenous People’s History of the United States" by Roxanne Dunbar-Ortiz