The Civil War was fought because Lincoln refused to allow the South to go in peace. Other Republican leaders and certain Northern business interests played key roles in the decision to use force, but ultimately Lincoln was the one who had to make the decision, and he chose to launch an invasion. The fighting and dying started when federal armies invaded the South. That’s why most of the battles were fought in the Southern states. If Lincoln had not launched an invasion, there would have been no war.
The Confederacy did not want war. One of the first things Jefferson Davis did after assuming office as president of the Confederacy was to send a peace delegation to Washington, D.C., in an effort to establish friendly ties with the federal government (Cooper, Jefferson Davis, American, pp. 360-362; Kenneth Davis, Don’t Know Much About the Civil War, New York: HarperCollins Publishers, 1996, pp. 156-157). The Confederacy offered to pay the South’s share of the national debt and to pay compensation for all federal installations in the Southern states (Charles Roland, The Confederacy, University of Chicago Press, 1960, p. 28; Patrick, Jefferson Davis and His Cabinet, p. 77; William C. Davis, Look Away! A History of the Confederate States of America, New York: The Free Press, 2002, p. 87). The Confederacy also announced that Northern ships would continue to enjoy free navigation of the Mississippi River (Hummel, Emancipating Slaves, Enslaving Free Men, p. 138; Davis, The Rise and Fall of the Confederate Government, Volume 1, pp. 210-213). Yet, Lincoln rejected all Confederate peace offers and insisted that federal armies would invade if the Southern states didn’t renounce their independence and recognize federal authority (and Lincoln specified that this included paying the federal tariff).
“Why,” one may ask, “did Confederates sometimes refer to themselves as ‘rebels’?” Actually, many Confederates resented that term (see, for example, Jefferson Davis, The Rise and Fall of the Confederate Government, Volume 1, pp. 282-284). Those Confederates who described themselves as “rebels” did so in sarcastic defiance and only in the sense that they were “rebelling” against being invaded and subjugated. Lincoln, on the other hand, labeled Confederates as “rebels” in order to reinforce his fraudulent claim that the South was trying to destroy democratic government.
It should be pointed out that many Northern citizens opposed the war and believed the South should be allowed to leave in peace. Dozens of Northern newspapers expressed the view that the Southern states had the right to peacefully leave the Union and that it would be wrong to use force to compel them to stay. Even President James Buchanan told Congress in an official message shortly before Lincoln assumed office that the federal government had no right to use force against the seceded states.
Source,
http://www.mtgriffith.com/web_documents/southernside.htm