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Which countries fought for the Allies in World War I?

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20th-century international relations American naval scholar Alfred Thayer Mahan, undated photo.

In the context of World War I, the Allied powers were a coalition of nations that opposed the Central Powers. The original core of this alliance, known as the Triple Entente, consisted of the British Empire, France, and Russia.12

As the conflict progressed, other nations joined the Allied cause. Italy entered the war on the side of the Allies in 1915, and the United States joined in 1917, though the U.S. technically operated as an "Associated power" to maintain political independence. Russia withdrew from the alliance following the Russian Revolution and its subsequent peace treaty with the Central Powers.13

By the time the Treaty of Versailles was signed in 1919, a total of 27 "Allied and Associated Powers" were recognized, including:

Belgium, Bolivia, Brazil, China, Cuba, Czechoslovakia, Ecuador, Greece, Guatemala, Haiti, the Hejaz, Honduras, Japan, Liberia, Nicaragua, Panama, Peru, Poland, Portugal, Romania, the Serb-Croat-Slovene State, Siam, and Uruguay.13