Post World War II saw major changes in Germany and Japan. Germany was divided into East and West, with the Western part under American, British, and French control and aiming to rebuild. The Nuremberg trials prosecuted Nazi leaders for war crimes. Japan lost over 10% of its population and had its military demobilized under American occupation led by Douglas MacArthur, who helped establish a new democratic constitution. War crime trials also took place in Japan. The United Nations was formed with the US, USSR, UK, France and China as permanent Security Council members.