The alliance formed in the early 20th century as a counter to the Axis Powers during World War II was the Allied Powers. This coalition initially included major powers such as the United States, the Soviet Union, and the United Kingdom, along with various other nations that opposed Axis aggression. The Allies worked together to combat the military advances of Germany, Italy, and Japan. Their collaboration was essential in coordinating military strategies, resources, and diplomatic efforts, ultimately leading to the defeat of the Axis Powers and the establishment of a post-war order in Europe and Asia.