Well it is plain to EVERYONE else that they DID exsist and the conflict was between two nations rather than factions within the SAME nation as you contend but, I guess, the old saw which goes "There are none so blind as those who will not see" is true in your case.
Really? Who? What nation recognized the confederacy as an independent nation and dealt with them on that basis? Nobody. Calling yourself a nation doesn't make you one. You can go around calling yourself the Grand High King of the Universe, but unless someone starts bowing and calling you 'Your Majesty" then your just another nut.