Unrecognized state in North America (1861–1865)
Source (Wikipedia): Confederate States of America

The Confederate States of America (CSA), commonly referred to as the Confederate States (C.S.), the Confederacy, or the South, was an unrecognized breakaway republic in the Southern United States that existed from February 8, 1861, to May 5, 1865. The Confederacy was composed of eleven U.S. states that declared secession; South Carolina, Mississippi, Florida, Alabama, Georgia, Louisiana, Texas, Virginia, Arkansas, Tennessee, and North Carolina; they warred against the United States during the American Civil War.