Many Americans have conflicting opinions on the main cause of the American Civil War, which can fuel misleading narratives on the issue. 

These contrasting viewpoints can be sorted into two basic camps: those who believe a desire for strengthened states' rights caused the Civil War, and those who believe the war was started solely — or most centrally — in defense of slavery. One 2023 YouGov poll finds that most Americans fall into the second camp (56%), with far fewer Americans identifying states’ rights as the overarching cause of the war (28%).

Nikki Haley’s Comments About the Cause of the Civil War

Although the Civil War was resolved over 150 years ago, the national debate surrounding its cause remains prominent in today’s political landscape. In December 2023, the Civil War debate reentered political discourse following comments from presidential hopeful Nikki Haley at a New Hampshire town hall event in late December. 

Following a question asking what the cause of the Civil War was, Haley failed to mention slavery as a central catalyst, instead citing “how government was going to run - the freedoms and what people could and couldn't do” as the cause for the war – thus promoting a states’ rights perspective. 

Although Haley later clarified her stance to include slavery as a central cause, her comments sparked bipartisan criticism, including comments from former President Donald Trump, who said “slavery is sort of the obvious answer.” 

What Caused the Civil War?

Conflicting perspectives on the Civil War’s origins are mostly rooted in cultural perspectives rather than party affiliation. For some Americans with cultural ties to the Southern United States, the Confederacy is a central component of their heritage, and they hold pride in their ancestors for defending against northern invaders; they put far less emphasis on the role of slavery as a cause of the Civil War. 

Today, many historians agree that slavery was at the heart of the conflict – more so than other political concerns, though some dissent from this view. Historically, the perspective that slavery was central was endorsed by political leaders like Confederate Vice President Alexander H. Stephens, who deemed the institution of “African Slavery” as the “immediate cause” for the South’s secession from the Union. The states of Texas, Mississippi, South Carolina, and Georgia all mention slavery early and frequently in their respective declarations of secession. The words "slave" or "slavery" appear more than 80 times across those declarations. Terms like "tariffs," "taxes," "territory," and "rights," as they pertained to states' concerns, appear far less.

Mississippi was most explicit in its concerns, explaining, “our position is thoroughly identified with the institution of slavery…a blow at slavery is a blow at commerce and civilization.”  

These concerns were not uniform, though. Confederate leader Robert E. Lee opposed secession but was more driven by loyalty to his home state of Virginia. Lee owned slaves until at least 1852, but in 1856, wrote that slavery “is a moral & political evil.”

Some argue economic concerns hold greater responsibility for the war's outset, pointing to taxation as the conflict’s fundamental instigator. Adherents to this perspective typically cite the Tariff Act of 1861, known as the “Morrill tariff,” specifically as a central catalyst – an import tariff that imposed rates as high as 47%. The burden of this tariff fell largely on the shoulders of import-dependent Southerners, making the tariff hugely unpopular in the South. At the same time, the North favored the tariff as a means of protecting its manufacturing industry, and some historians point out that the majority of tax revenue from this law was being spent on the North, leaving the South behind. 

From this perspective, it was oppressive economic policy that pushed the South to secede from the Union, and Lincoln utilized abolition as a disingenuous moral talking point for war, believing a war for emancipation was more glamorous than a war for taxes.             

Similarly, neo-Confederate organizations often promote a pro-South historical interpretation of the Civil War known as the “Lost Cause” perspective, a historical narrative that rose to popularity decades after the war’s end. This perspective minimizes slavery’s central role in the Civil War, instead arguing that the South was forced into secession as a result of the federal government’s infringement on states’ rights – like taxation – and nobly fought in opposition to tyranny and federal overstep. This perspective is popular among some Southerners, but is considered myth by many scholars.  


States who moved to secede mentioned the issue of slavery in their declarations of secession often, and far more than they mentioned any other single issue. Some of these states also listed various other factors, including economic conditions and government policies.

Some historical documentation particularly emphasizes the importance of slavery as a cause of the Civil War, with several states expressly noting slavery as a central cause for their secession, and some Confederate leaders, like Alexander H. Stephens, referencing slavery as a key motivation for the establishment of the Confederacy. 

Neo-Confederate organizations, among other groups, adhere to the Lost Cause perspective, which emphasizes the defense of states’ rights, especially around economics, as the main catalyst for the Civil War.    

Although discourse regarding the root cause of the Civil War tends to fall upon party lines – as Republican politics dominate the South – the debate could be better characterized as a cultural conflict rather than a distinctly partisan conflict. Still, as Republican candidates aim to appeal to Southern voters in the months approaching the 2024 federal election, ideas surrounding the Civil War are likely to remain in political conversation.   

This piece was reviewed by Henry A. Brechter, AllSides Editor-in-chief (Center bias), Joseph Ratliff, AllSides Content Designer and News Editor (Lean Left bias), and Julie Mastrine, Director of Media Bias Ratings and Marketing (Lean Right).