It's a little hard to tell from your photos (and my neck only tips so far) but this looks like it might be a receipt or a bill from a gas company.
With all due respect to our Southern neighbors, the War ended officially in 1865 but continued on in a much smaller scale through 1866.
Actually it ended "officially" in April of 1866, with Andrew Johnson's declaration. For all intents and purposes it ended in 1865 with the surrender of the major armies, the most realistic of which being Gen. Johnston's army and the last of which being Gen. Kirby Smith's in Texas in late May of 1865. To say that the Civil War itself continued after that is at best a bit of a stretch to say the least. Texas yada, yada, yada. It ended in 1865.
The horrific loss of life on the battlefields is indeed mercifully over. The unimaginable horror of homes and fields and towns being burned and ravaged is over and done. Most of us "Southern neighbors" have put the Lost Cause behind us and moved on with our lives and with living. We just want to live and let live and ask only that others do the same. Unfortunately we're seeing once again an uptick in political correctness that seeks to abolish a heritage. Enough already. We ask only for respect and courtesy as we offer the same. Every time I visit the nearby Vicksburg National Battlefield Park I come away with tears for the dead, military and civilian. It's over and price has been paid on BOTH sides. Okay, I've turned the emotion button off, hoping I've offended no one.