The Confederate States of America was a short-lived nation on the North American continent of the planet Earth. It was made up of states, beginning with South Carolina, that had declared themselves separate, or seceded, from the United States of America.
It existed from 1861 to 1865, during which time it was wholly concerned with establishing its legitimacy through a war with the United States. Its capital was Richmond, Virginia and its president was Jefferson Davis. (PROSE: Blood and Hope)
In 1863, the Third Doctor gave U.S. President Abraham Lincoln a sketched map that he had made of the Confederate lines at Gettysburg. Lincoln gave the map to General Ulysses S. Grant, thus helping the Union Army to win the Battle of Gettysburg. (COMIC: Backtime)
Following the war, the former states of the Confederacy were re-absorbed into the United States of America — although President Lincoln's government, judging from his final public speech, did not consider that they had ever, technically, seceded. (PROSE: Blood and Hope)
In a parallel universe visited by the Third Doctor, the Confederate States won the American Civil War. In the war's aftermath, the American Confederation was established. (PROSE: The Face of the Enemy)