squick on Family Tree Circles

My great great grandfather George Thompson was from Missouri and born in the mid 1800's. He married a full blood chickasaw indian who went by the name of Elizabeth. I am trying not only to find George's fathers name but also who Elizabeth's family was. George and Elizabeth divorced and Elizabeth moved with their three boys to Southern Oklahoma. I do not know if George had any siblings. Is there anyone out their that has heard of this Thompson?