- Date:
- September 3, 1939 - September 2, 1945
Allied powers
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Who were the Allied powers in World War II?
The Allied powers were a group of countries that opposed the Axis powers during World War II. The main Allied powers were Great Britain, France, the Soviet Union, the United States, and China.
More broadly, the Allies included all the wartime members of the United Nations who signed the Declaration by United Nations on January 1, 1942. These original signers included Australia, Belgium, Canada, Costa Rica, Cuba, Czechoslovakia, the Dominican Republic, El Salvador, Greece, Guatemala, Haiti, Honduras, India, Luxembourg, the Netherlands, New Zealand, Nicaragua, Norway, Panama, Poland, South Africa, the United Kingdom, the United States, and Yugoslavia.
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Which major countries were part of the Allied powers?
During World War II, the Allied powers opposed the Axis powers, which included Germany, Italy, and Japan. The main Allied countries, known as the "Big Four," were the United Kingdom, the Soviet Union, the United States, and China.
The Allies also included countries that signed the Declaration by United Nations on January 1, 1942, such as Australia, Belgium, Canada, Costa Rica, Cuba, Czechoslovakia, the Dominican Republic, El Salvador, Greece, Guatemala, Haiti, Honduras, India, Luxembourg, the Netherlands, New Zealand, Nicaragua, Norway, Panama, Poland, South Africa, and Yugoslavia. Later wartime signers included Mexico, the Philippines, Ethiopia, Iraq, Brazil, Bolivia, Iran, Colombia, Liberia, France, Ecuador, Peru, Chile, Paraguay, Venezuela, Uruguay, Turkey, Egypt, Saudi Arabia, Syria, and Lebanon.
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Why did these countries form an alliance during World War II?
During World War II, the Allied powers united in opposition to the Axis powers, which included Germany, Italy, and Japan. The alliance began with the United Kingdom and France pledging to aid Poland if it were invaded by Germany. When Germany attacked Poland in 1939, they declared war, and the British dominions followed suit.
As Germany invaded other countries, such as Denmark, Norway, Belgium, and the Netherlands, these nations also joined the Allies. The Soviet Union joined the Allied forces after Germany invaded in 1941. The United States joined after the attack on Pearl Harbor. The combined production capacity of the Allies, especially the U.S., was a major advantage, producing almost two-thirds of all Allied military equipment by the end of the war.
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How did the Allied powers work together to fight the Axis powers?
The Allied powers in World War II, including the United Kingdom, the Soviet Union, the United States, and China, united against the Axis powers. When Germany invaded Poland on September 1, 1939, the United Kingdom and France declared war, marking the beginning of their alliance.
The Soviet Union joined the Allies after Germany invaded in June 1941, receiving support from the American lend-lease program. The United States officially entered the Allied fold after the Japanese attack on Pearl Harbor in December 1941.
President Franklin D. Roosevelt and British Prime Minister Winston Churchill established the Combined Chiefs of Staff to facilitate Anglo-American cooperation. This system of consultation ensured the coordination of military efforts. The Allies employed strategies such as strategic bombing to weaken the Axis powers.
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What were some important meetings or conferences held by the Allied leaders?
Several significant conferences were held by Allied leaders during World War II to strategize and coordinate their efforts.
Key meetings:
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Arcadia Conference In December 1941, Winston Churchill and Franklin D. Roosevelt met to reaffirm the "Europe first" strategy.
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Casablanca Conference In January 1943, Roosevelt and Churchill met to plan the invasion of Sicily and agree on the concentrated bombing of Germany. They also declared the Allies would accept only unconditional surrender from the Axis powers.
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TehrÄn Conference In November 1943, Roosevelt, Churchill, and Joseph Stalin met to discuss the opening of a second front in Western Europe. Stalin also stated that the Soviet Union should retain the frontiers provided by the German-Soviet Nonaggression Pact of 1939.
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Yalta Conference In February 1945, Roosevelt, Churchill, and Stalin planned the final defeat and occupation of Nazi Germany. They also discussed how to deal with the defeated or liberated countries of eastern Europe.
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Potsdam Conference In July 1945, Harry S. Truman, Churchill (and later Clement Attlee), and Stalin discussed the administration of defeated Germany, the boundaries of Poland, and the Soviet Unionâs role in eastern Europe.
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How did the actions of the Allied powers lead to the end of World War II?
The Allied powers, including the United Kingdom, the Soviet Union, the United States, and China, played a crucial role in ending World War II. Their combined efforts led to the defeat of the Axis powers.
The Normandy landings on June 6, 1944, opened a second front in Europe, which was a decisive move against Germany. Simultaneously, the Red Army advanced from the east, reclaiming territory and putting pressure on Germany. The Allies converged on Berlin, leading to Adolf Hitler's suicide on April 30, 1945, and Germany's surrender on May 8.
In the Pacific, the American "island hopping" campaign crippled Japanese installations. The atomic bombings of Hiroshima and Nagasaki in August 1945 forced Japan to accept Allied surrender terms, leading to Japan's formal surrender on September 2, 1945.
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Allied powers, coalition of countries that opposed the Axis powers (led by Germany, Italy, and Japan) during World War II. The principal members of the Allies were the United Kingdom, the Soviet Union, the United States, and China (the âBig Fourâ), as well as France while it was unoccupied. The Allies also included every other signatory to the Declaration by United Nations (January 1, 1942): Australia, Belgium, Canada, Costa Rica, Cuba, Czechoslovakia, the Dominican Republic, El Salvador, Greece, Guatemala, Haiti, Honduras, India, Luxembourg, the Netherlands, New Zealand, Nicaragua, Norway, Panama, Poland, South Africa, and Yugoslavia. Later wartime signers were Mexico, the Philippines, Ethiopia, Iraq, Brazil, Bolivia, Iran, Colombia, Liberia, France, Ecuador, Peru, Chile, Paraguay, Venezuela, Uruguay, Turkey, Egypt, Saudi Arabia, Syria, and Lebanon.
The Allies began as an agreement between Poland, the United Kingdom, and France that the latter two would come to Polandâs aid if it were invaded by Germany. When Germany did attack on September 1, 1939, the United Kingdom and France fulfilled their promise, declaring war against Germany on September 3. The independent British dominions of Australia, Canada, New Zealand, and South Africa followed the United Kingdomâs lead, declaring war either that same day or a few days later.
Denmark and Norway joined the Allies the next year when Germany invaded both countries on April 9, 1940. So too did the Low Countries (Belgium, the Netherlands, and Luxembourg) that May, once Germany repeated its World War I strategy of moving its forces through those countries to invade France. All these new partnerships were short-lived, however, as Germany swiftly conquered each country. The same sequence of events would play out again in southeastern Europe: Greece and Yugoslavia joined the Allies on October 28, 1940, and April 6, 1941, respectively, but were soon occupied. With France surrendering on June 22, 1940, the United Kingdom and its former colonies were effectively the only Allies in action for over a year, from mid-1940 to mid-1941.
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It was on June 22, 1941, that the British received an unexpected gift: the German invasion of the Soviet Union. This attack resulted in an Anglo-Soviet treaty on July 12, 1941âand unlike the smaller nations that had been so quickly overrun by the German war machine, the Soviet Union was capable of not only surviving its initial ambush but also helping the Allied cause beyond its own borders (e.g., invading Iran to ensure that its oil could not be used to fuel Axis vehicles). With support from the American lend-lease program, the Soviet Union became a nightmare for the German military. Eventually, its forces would push the Germans all the way back to Berlin.
On December 7 (December 8 in Asia), 1941, Japan attacked American, British, and Dutch military bases in the Pacific, East Asia, and Southeast Asia. For reasons still debated today, Germany declared war on the United States as well, on December 11. Where once the United States had participated in the war only as a source of arms and other supplies for the Alliesâserving as what Pres. Franklin. D. Roosevelt memorably called âan arsenal of democracyââthese aggressions brought it fully into the Allied fold.
The attacks were perhaps the Axis powersâ greatest mistake. As in World War I, U.S. production capacity dwarfed that of any other country with which it was allied or fought. By the end of the war, the U.S. would produce almost two-thirds of all the Alliesâ military equipment. The U.S. also had the population to contribute a large number of troops, mobilizing over 16 millionâmore than any other Allied power save the Soviet Union. Where the U.S. went, much of the Western Hemisphere followed. Countries that immediately declared war on members of the Axis powers in the wake of Japanâs attack included Costa Rica, Cuba, the Dominican Republic, El Salvador, Guatemala, Haiti, Honduras, and Panama. Brazil joined on August 22, 1942, Mexico on May 22, 1942. Bolivia became an official member as well on April 7, 1943, but its government was overthrown in a coup shortly thereafter.
After this new influx of partners, the Allied roster remained mostly stable until near the end of the war. Countries liberated from Axis occupation renewed their membership in the Allies. In 1945 the inaugural meeting of the United Nationsâformally called the United Nations Conference on International Organization (UNCIO)âled a number of previously neutral countries such as Saudi Arabia to join the Allies, as the organizing countries made allying with them against the Axis a precondition for attending. The Allies therefore ended the war with 47 member states, all of which would become charter members of the United Nations when that bodyâs charter was signed on June 26, 1945.
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