The Grand Alliance was an alliance made during World War II, which joined together the United States (led by Franklin Roosevelt), the Soviet Union (led by Joseph Stalin) and Great Britain (led by Winston Churchill). Roosevelt, Stalin and Churchill are often known as "The Big Three" or the Allies of World War II. The Grand Alliance is the title of volume three of Churchill's book The Second World War, which formed the basis of his Nobel Prize for Literature. It was essentially an alliance of necessity, as all three needed to join together in order to defeat the threat of Nazi Germany.