The Empire of Japan, also known as the Japanese Empire or Imperial Japan, was the period of Japanese history spanning 79 years, starting with the Meiji Restoration on 3 January 1868, and ending with ratification of the Constitution of Japan on 3 May 1947. From August 1910 to September 1945, it included mainland Japan, Okinawa, the Kurils, Karafuto, Korea, and Taiwan. The South Seas Mandate and concessions were de jure not internal parts of the empire but dependent territories. In the closing stages of World War II, with Japan defeated alongside the rest of the Axis powers, the formalized surrender was issued on 2 September 1945, in compliance with the Potsdam Declaration of the Allies, and the empire's territory subsequently shrunk to cover only mainland Japan. However, Okinawa was later returned to Japan in 1972.