Your best bet would probably be to get a copy of the Lonely Planet Japan book and read the chapter on Okinawa.

"Results": [
    {
        "TypeName": "LOC",
        "Text": "Japan",
        "Start": 67,
        "End": 72
    },
    {
        "TypeName": "LOC",
        "Text": "Okinawa",
        "Start": 102,
        "End": 109
    }
]