Allies During WWII

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Roughly twenty-one years after the end of World War I, the second world war began. World War II found many of the same allies of World War I teaming up against the reformed Central Powers, which were renamed the Axis Powers in World War II. As before, Great Britain and France led the allies at the start, this time joined by Poland, a country that did not exist as an independent nation until the end of WWI. Independent nations of the British Empire, such as Canada, Australia, and South Africa, joined the Allies shortly thereafter. Over time, more than twenty Allies would join the cause as the number of countries involved in WWII continued to expand, engulfing even countries that have no military.

The Big Three Allies and the Four Powers of World War II

Three of the most powerful Allies entered the war—or at least the Allied cause—late, but had a massive impact when they did. First of these was Russia, which actually began WWII as one of the Axis Powers, having signed a non-aggression pact with Germany. In fact, Russia had assisted Germany in its initial invasion of Poland in 1939. However, Germany broke the non-aggression pact itself and attacked Russia in 1941, prompting Russia to switch its allegiance to the Allies.

As it had in the first World War, the United States spent the early portion of World War II attempting to distance itself from the affairs of Europe and join the list of countries that remained neutral in WWII. That all changed when the Japanese bombed the U.S. Naval base at Pearl Harbor, Hawaii in December 1941. In response, the United States entered the war in earnest, participating heavily in both the European and Pacific fronts.

China also joined the Allies in December 1941, an important development even though the country had already been at war with Axis power Japan since 1937. The United Kingdom, Russia, and the United States would come to be known as the "Big Three," and also (with China included) as the "Four Powers." They remain military powers today, with three of the largest militaries of any country on Earth, as well as some of the largest nuclear arsenals in the world. Once World War II ended, the Allies would establish the United Nations, an organization that today includes 193 countries and two observer states.

List of Allied Countries in World War II:

Country Date Joined Country Date Joined Country Date Joined
Argentina 27 March 1945 Finland* 15 Sept. 1944 Oman 10 Sept. 1939
Australia 3 Sept. 1939 France 3 Sept. 1939 Panama 7 Dec. 1941
Belgium 10 May 1940 Greece 28 Oct 1940 Paraguay 7 Feb. 1945
Bolivia 7 Apr. 1943 Guatemala 9 Dec. 1941 Peru 12 Feb. 1945
Brazil 22 Aug. 1942 Haiti 8 Dec 1941 Philippines 8 Dec 1941
British India 3 Sept. 1939 Honduras 8 Dec. 1941 Poland 1 Sept. 1939
Bulgaria* 8 Sept. 1944 Iran 9 Sept. 1943 Romania* 25 Aug. 1944
Canada 10 Sept. 1939 Iraq 16 Jan. 1943 Saudi Arabia 1 Mar. 1945
Chile 11 April 1945 Lebanon 27 Feb. 1945 South Africa 6 Sept. 1939
China 9 Dec 1941 Italy* 10 Oct. 1943 South Korea* 10 Dec. 1941
Colombia 26 July 1943 Liberia 27 Jan. 1944 Soviet Union 22 June 1941
Costa Rica 8 Dec. 1941 Luxembourg 10 May 1940 Syria 26 Feb. 1945
Cuba 9 Dec. 1941 Mexico 22 May 1942 Turkey 23 Feb. 1945
Czechoslovakia* 16 Dec. 1941 Mongolia 1 Aug 1945 United Kingdom 3 Sept. 1939
Denmark 8 Apr. 1940 Nepal 4 Sept. 1939 United States 8 Dec. 1941
Dominican Rep. 8 Dec. 1941 Netherlands 10 May 1940 Uruguay 15 Feb. 1945
Ecuador 2 Feb. 1945 New Zealand 3 Sept. 1939 Venezuela 15 Feb. 1945
Egypt 24 Feb. 1945 Nicaragua 8 Dec. 1941 Vietnam (Viet Minh) 7 Dec. 1941
El Salvador 8 Dec. 1941 Norway 8 Apr. 1940 Yugoslavia 6 Apr. 1941
Ethiopia 14 Dec. 1942

* Notes:

  • Bulgaria began the war as an Axis nation.
  • Czechoslovakia's legitimate government declarted its allegiance while in exile, as the country was occupied.
  • Finland fought alongside Germany and against Russia in the Continuation War from 1941-1944 and did not declare war on Germany until 3 March 1945. However, the declaration was made retroactive to 15 September 1944.
  • Italy and Romania began the war as Axis nations.
  • South Korea's government was provisional at the time of its declaration.
  • Vietnam's allegiance was declared by the Viet Minh, a government that was revolutionary at the time.

Allies During WWII

Allies During WWII