American Civil War alternate histories are alternate history fiction that focuses on the Civil War ending differently or not occurring. The American Civil War is a popular point of divergence in English-language alternate history fiction. The most common variants detail the victory and survival of the Confederate States. Less common variants include a Union victory under different circumstances from actual history, resulting in a different postwar situation; black American slaves freeing themselves by revolt without waiting for Lincoln's Emancipation Proclamation; a direct British and/or French intervention in the war; the survival of Lincoln during John Wilkes Booth's assassination attempt; a retelling of historical events with fantasy elements inserted; the Civil War never breaking out and a peaceful compromise being reached; and secret history tales. The point of divergence in such a story can be a "natural, realistic" event, such as one general making a different decision, or one sentry detecting an enemy invasion unlike in reality. It can also be an "unnatural" fantasy/science fiction plot device such as time travel, which usually takes the form of someone bringing modern weapons or hindsight knowledge into the past. Still another related variant is a scenario of a Civil War that breaks out at a different time from 1861 and under different circumstances (such as the North, rather than the South, seceding from the Union).

American Civil War alternate histories are one of the two most popular points of divergence to create an alternate history in the English language, the other being an Axis victory in World War II.

Depictions of the later development of a victorious Confederacy vary considerably from one another, especially on two major interrelated issues: the independent Confederacy's treatment of its black population and its relations with the rump United States in the North.

Scenarios The South wins the Civil War, and slavery still exists as of the time of the story. Examples include the 2004 mockumentary C.S.A.: The Confederate States of America, where the United States is annexed by the Confederate States and slavery continues. In Ben Winters' Underground Airlines, slavery has remained legal in the "Hard Four" (Alabama, Louisiana, Mississippi and a unified Carolina) and slaves are controlled by electronic device implanted in their spines. Its name evokes the Underground Railroad in relations to its setting. The novel attracted praise for exploring racism through the alternate-history mechanism.

In Hallie Marshall: A True Daughter of the South (1900) by Frank Williams, the earliest known Civil War alternate history, the Confederacy won by mobilizing black slaves to its army, their participation turning the tide at Gettysburg. Thirty years later, the independent Confederacy is full of happy, well-treated black slaves feeling perfectly content under the benevolent, paternalistic planters, comparing favorably with the rump United States, which is torn by a brutal class struggle, with nominally free factory workers protesting inhumane working conditions or starving in unemployment. In Gray Victory, set in the immediate aftermath of the war, the Confederacy is faced with both subversion by Northern Abolitionists and the increasing organization and assertiveness of Black Southerners, and the story gives the clear impression that no matter who wins, the end of slavery is inevitable.

Slavery ends in the South in name only, or minorities are oppressed into low socio-economic parts of society, such as in The Guns of the South. Freeing the slaves is attributed to Robert E. Lee, who becomes the second Confederate President. It is logical to assume that his prestige would have run high and made him a plausible candidate to succeed Jefferson Davis, but the position he would have taken regarding slavery is the subject of some debate. However, ending slavery would not necessarily provide equality for Black Southerners, and Bring the Jubilee has blacks, despite Lee's grand gesture, remaining disenfranchised into the 20th century, as are people from Latin America, who are annexed by the Confederacy. The rump United States is completely broken down by its defeat and becomes an impoverished and backward country while the Confederacy goes on to annex everything to its south as far as Tierra del Fuego (except the Republic of Haiti) and become a major world power. In Harry Turtledove's Southern Victory series, it is President James Longstreet who abolished slavery as a prerequisite for retaining British and French support for the Confederacy in the Second Mexican War, but blacks remain an underclass that is very oppressed and discriminated against, denied basic civil rights, and are not even allowed to have surnames. In later volumes of the series, the blacks rise in a brutal armed revolt, called the Red Rebellion, during the Great War, which leads to a Holocaust-like genocide.

A more optimistic result in The Guns of the South and several other works has both nations settle down and have reasonably good neighborly relations within a few years of the war's end and, in some cases, agree to reunite as one nation after 50 or 100 years of being apart. If the South Had Won the Civil War by MacKinlay Kantor has reunification come later: in the 20th century, the United States, the Confederate States and Texas, which seceded from the CS, become economically integrated and in both World Wars all fight against Germany as close allies. After the Second World War, all three feel threatened by Soviet missile bases and armored brigades in Alaska, which was never purchased from Russia. They announce formal reunification in 1961, on the precise centennial of Fort Sumter. Conversely, a GURPS game setting book presents a 1993 in which the US and the CS still watch each other warily across an armed border that stretches to the Pacific.

In Southern Victory, the US and the CS develop into hereditary enemies that go to war again every decade or two, spend the rest of the time preparing for new war, and become entangled in webs of worldwide military alliances. Southern Victory has both drawn into the Great War. They open an American front of trench warfare that is every bit as terrible as the one in Europe, and a generation later go to war yet again with the Confederacy developing a murderous tyranny similar to Nazi Germany. Conversely, the 1914 of "A Hard Day for Mother", in Alternate Generals 1 by William R. Forstchen, sees an amicable treaty of reconciliation and voluntary reunification between the two nations.

We Will Water Our Horses in The Mississippi: A.S. Johnson vs. U.S. Grant by James R. Arnold, Texan Confederate General Albert Sidney Johnston survived a fatal wound. This narrative is positioned within a broader series of alternative historical analyses, particularly those less recognized in the context of the Civil War, considering hypothetical scenario such as Confederate victories deciding the outcome of the western theater and strategic river fort.https://warhistory.org/article/what-if-we-will-water-our-horses-in-the-mississippi

Literature Novels 1862 by Robert Conroy. After the Trent Affair, the United Kingdom joins the Civil War on the side of the Confederacy. Abraham Lincoln, Vampire Hunter, by Seth Grahame-Smith, recasts the Civil War as a war on vampires that use slaves as a food source. The novel was later made into a film of the same name. "Beyond the Wildest Dreams of John Wilkes Booth" by Jay Winik, first printed in What Ifs? of American History, a scenario in which John Wilkes Booth assassinates not only Lincoln but also Andrew Johnson and William H. Seward. Bring the Jubilee by Ward Moore Britannia's Fist (trilogy) by Peter Tsouras. Britain and France enter the War in 1863 when British-built warships enter the Confederate Navy, instead of being seized by British forces before they could service, as really happened. Crosstime Traffic series by Harry Turtledove visits many alternate realities and briefly mentions a few in which the South won the Civil War. The fourth volume, The Disunited States of America, focuses on an alternate reality in which the adoption of the Articles of Confederation resulted in the dissolution of the United States by the 1800s. There were frequent small localized wars between states (such as Ohio versus Virginia, Massachusetts versus Rhode Island) but no single massive civil war. The Difference Engine by William Gibson and Bruce Sterling. In an alternate reality in which Charles Babbage successfully develops an analytical engine by 1824, Britain interferes in North American affairs to prevent the rise of the United States as a world power. By 1855, the Confederate States had seceded from the Union with other breakaway states including a Texan Republic, a Californian Republic and a Communist Manhattan Commune; there is also a Native American-dominated terra nullius in the Great Plains. Dirk Pitt series: Volume 11: Sahara by Clive Cussler. The series's recurring MacGuffin in which the heroes discover an astounding secret history, involves the Lincoln assassination in this one. It is a brief side plot that is only tenuously related to the main adventure and is completely left out of the film adaptation of the novel. Fire on the Mountain by Terry Bisson. Instead of a Civil War breaking out between North and South, there is a massive successful slave revolt in the Deep South, with blacks creating their own separate nation called "Nova Africa," which leads to Socialist revolutions in France, the United States, Ireland, and Russia. Gettysburg: An Alternate History by Peter Tsouras. A counterfactual account of an even more decisive Union victory at The Battle of Gettysburg Gettysburg: A Novel of the Civil War, Grant Comes East, and Never Call Retreat: Lee and Grant: The Final Victory by Newt Gingrich, William R. Forstchen, and Albert S. Hanser - the South wins the Battle of Gettysburg as in the classic Bring the Jubilee, but General Ulysses Grant manages to snatch victory from the jaws of defeat, and the North wins the war even quicker than in actual history. Gray Victory by Robert Skimin The Guns of the South by Harry Turtledove. Members of the Afrikaner Weerstandsbeweging travel back in time from 2014 South Africa to the Confederacy in 1864. They supply Lee's Army of Northern Virginia with AK-47s and small amounts of other technologies, resulting in a Confederate victory. The Impeachment of Abraham Lincoln by Stephen L. Carter. Lincoln survives his assassination at Ford's Theatre in 1865 but is impeached by Congress. "Lee at the Alamo" by Harry Turtledove. A story published online at here.http://www.tor.com/2011/09/07/lee-at-the-alamo/ The Lost Regiment series by William R. Forstchen. A Union Army regiment is transported into an alien world, that faces off against aliens such as the Tugar and the Bantag. A Rebel in Time by Harry Harrison. A racist army officer goes back in time to bring about a Confederate victory. Russian Amerika by Stoney Compton. The backstory is only vaguely defined, but the point of divergence seems to be a Confederate victory in the 1860s. The Mechanical War by N.G. Mays, The setting re-imagines the American Civil War with advanced mechanical weapons and aerial reconnaissance, showing a conflict changed by fast industrial innovation.https://books.google.com/books/about/The_Mechanical_War.html?id=9Evt0QEACAAJ Shattered Nation: An Alternate History of the American Civil War (trilogy) by Jeffrey Evan Brooks. The series focuses on the Confederacy winning its independence in 1864 by achieving victory at the Battle of Atlanta, thanks to a telegram that keeps Joseph E. Johnston as general of the Army of Tennessee. The Shiloh Project by David Poyer