Okinawa, Japan: The People, History, World War II, Culture and Tradition. Travel and Tourism : Global Print Digital : 9781912483112 : 1912483114 : 14 Oct 2017 : Okinawa, Japan. The People, History, World War II, Culture and Tradition. Travel and Tourism. Before Okinawa, there was Ryukyu, an independent kingdom ruled by its kings, its people seafarers prospering through trade with China and other neighboring countries. In 1609, Ryukyu was invaded by Satsuma Han forces and incorporated into mainland Japan's Tokugawa Era "bakuhan" feudal regime. Okinawa prefecture was created in 1879 when Japan's new Meiji government abolished hans (feudal domains).During the Pacific War, the people of Okinawa were engulfed in the war's only land battle on Japanese territory. After the war, America retained control of Okinawa until 1972 when sovereignty reverted to Japan. Japan's only prefecture in the subtropical latitudes, Okinawa enjoys a mild climate all year round. With schools of brightly tropical f