The Yalta Conference was a meeting of the Allied leaders of World War II in February 1945, held in the Soviet Union. It was attended by U.S. President Franklin D. Roosevelt, British Prime Minister Winston Churchill, and Soviet leader Joseph Stalin. The CAIRO Conference was a meeting of the Allied leaders of World War II in November 1943, held in Egypt. It was attended by U.S. President Franklin D. Roosevelt, British Prime Minister Winston Churchill, and Chinese leader Chiang Kai-shek. Both conferences were important in determining the outcome of World War II.