The four main Allies in World War I were _____. Solution World War I was fought between July 18, 1914 and November 11, 1918. it was also known as The Great War. In World War I, there were two group of nations fighting with each other. One group is known as Allied powers or Allies while other group was known as Central Powers. Central Powers consists of Austria-Hungary, Turkey, and Germany while Allied Powers consists of Russian Empire, France, British Empire, and Italy and was later joined by United States as well. So, the four main Allies in World War I were British empire or Britain, Russian Empire or Russia, France, and Italy..