The Allied Powers of World War I, also known as the Allies, was a global alliance and the belligerent that opposed the Central Powers in World War I. It was succeeded 19 years later by the Allied Powers of World War II.
- The Allied Powers were built on the Triple Entente of 1907; the French Third Republic, the Russian Empire, and the British Empire.
- In 1915, Italy ended the Triple Alliance, an alliance between it, Austria-Hungary, and the German Empire, who went on to become the Central Powers, because of Austria-Hungary declaring war so rashly, and joined the Allied Powers.
- Serbia, Montenegro, Japan, Romania, Belgium, and Greece eventually joined as well.
- In response to the German Empire attacking international shipping and the Zimmerman Telegraph, the United States of America joined the Allies in 1917.