The Declaration by United Nations was the main treaty that formalized the Allies of World War II and was signed by 47 national governments between 1942 and 1945. On New Year's Day 1942, during the Arcadia Conference, the Allied "Big Four"—the United Kingdom, the United States, the Soviet Union, and China—signed a short document which later came to be known as the United Nations Declaration, and the next day the representatives of 22 other nations added their signatures.[1][2][3]