The movement emerged in 1945, after the end of the Pacific War. Some Ryukyuan people felt, as the Allied Occupation began, that the Ryukyus (Okinawa) should eventually become an independent state, instead of being returned to Japan.
The majority pushed for unification with the mainland, hoping that this would hasten the end of the Allied Occupation there].
The US-Japan Security Treaty was signed in 1951 as re-unification occurred, and providing for the continuation of the American military presence. This set the stage for renewed political movement for Ryukyu independence.