Any people anywhere, being inclined and having the power, have the right to rise up and shake off the existing government, and form a new one that suits them better. This is a most valuable, a most sacred righta right which, we hope and believe, is to liberate the world. Nor is this right confined to cases in which the whole people of an existing government may choose to exercise it. Any portion of such people that can may revolutionize, and make their own of so much of the territory as they inhabit.
They never became independent though
DiogenesLamp well knows that neither Lincoln nor any law anywhere, any time ever said: ownership of property changes just because some people get together to declare themselves "seceded".
The US Constitution provides that Congress disposes of Federal properties, but no Confederate ever approached Congress to negotiate anything regarding Federal properties in states which declared secession.
All of which DiogenesLamp well understands, but refuses to acknowledge.