This is a very rarely discussed period of Okinawan history, since it sort ot sits between the two giant shitstorms the battle of Okinawa and the US occupation. But the 3~4 years between 1945 and 1948~1949 changed Okinawan history immeasurably.
One of the things I've found was the honestly insane level of population increase between 1945 and 1950. Before WW2, only 500k or so people lived in Okinawa prefecture as a whole. After the war, the number dropped to almost 300k due to wartime casualties and people that evacuated beforehand, and over the next 5 years jumps to a previously unheard of 900k. You can probably contribute a decent chunk to the postwar baby boom, but almost certainly more than 300k Okinawans were repatriated from the mainland/other Japanese colonies.
I wonder if you could "choose" to stay on the Japanese mainland if you wanted or, the whole thing was borderline forced. And whether this whole thing was given even an ounce of thought because adding several hundred thousand people to an island where practically all arable land and buildings had been bombed into oblivion, and making it very difficult to leave has to be a terrible idea. It probably would have caused the mother of all housing crisis, and just made famines infinitely worse.
This might have contributed to local sentiment turning around so fast against the US occupation. Okinawa isn't the worst place to start an independence movement, and I would have given people like Nakasone Genwa a decent chance of maybe getting some degree of autonomy from Japan (think Puerto Rico), yet it died off almost as soon as it began. I wasn't able to find much credible explanation, but looking at the demographic trends made me realize a huge chunk of the population probably had nowhere to go and just wanted things to just go back to "normal".
by BallsAndC00k