The Confederate States Army ( GSA ) was organized in February 1861 to defend the newly formed Confederate States of America from military action by the United States government during the American Civil War . The Confederate States Army was the army of the Confederate States of America ( or `` Confederacy '' ) while the Confederacy existed during the American Civil War . On February 8 , 1861 , delegates from the seven Deep South states which had already declared their secession from the United States of America adopted the Provisional Constitution of the Confederate States of America .