Similarly, there may have been significant movements for Okinawan independence following its annexation, in the period prior to and during World War II. Following the war, the United States Occupation government took over control of Okinawa, and <b>Roosevelt told Chiang Kai-shek that he wants to returns Ryūkyū to China twice, but Chiang Kai-shek turned down this proposal for many reasons</b>. The Americans retained control over the Ryūkyū Islands until 1972, twenty years after the formal occupation of the rest of Japan had ended. There was pressure in 1945, immediately following the war, for the creation of a fully independent Ryūkyūan state, while later in the Occupation period there arose a strong movement not for independence but for a return to Japanese sovereignty.