The closest that I know of to what you were looking for is the Free State of Jones which formed in 1863 by a group of Confederate deserters in Jones County, Mississippi. Here's the Wikipedia article on it: https://en.wikipedia.org/wiki/Jones_...State_of_Jones
Matthew McConaughey starred in a movie about it last year. Although if you are looking for a good Civil War movie, don't bother. Its the usual Hollywood make believe.![]()