The "main event" leading to the secession of the Southern states and ultimately to the US Civil War was the constitutional and lawful election of Abraham Lincoln in 1860. The Democrats had split along sectional lines, and the new "third party" (the Republicans) won 40 percent of the vote, enough to win an Electoral College majority and the presidency. Since Lincoln did not even appear on the ballot of many Southern states, small wonder that the South felt alienated and outside the system that had previously accommodated them and their "peculiar institution" of slavery for so many years. To make matters worse, the Republicans were a strictly Northern party that opposed the expansion of slavery to areas where it did not exist.
In the hype and hysteria leading up the 1860 election, Southern opinion leaders were adamant in their opposition to Lincoln and the "Black Republicans." Many promised secession if the Republicans won, and South Carolina led the way in December of 1860, followed by ten more states by April of 1861. Four months later, South Carolina would fire the opening shots on the federal fortress of Fort Sumter in Charleston Bay, and the Civil War would begin.
Long before those opening shots, though, the events leading the Southern secession and the US Civil War were somewhat analogous to could be experienced in the break up of a shaky marriage. These events were both tensions and confrontations that led to what could only be regarded as "irreconcilable differences," except that the South wanted to depart in peace, but the North wanted to hold the relationship together by force.
The "marriage" between the North and South was shaky from the start. Founded on a compromise that allowed Southerners to count their slaves as three-fifths of a person, our constitutional government from the outset made a pact with slavery that would prove to be its undoing four score and eleven years later. The irreconcilable differences were also based on divergent economic and social development in both sections of our country, differences that were both complex and often intangible. The North was industrialized, steam-harnessed and capitalistic. The South's riches were in the land and the slaves who tilled the cotton. In fact, two-thirds of the estimated $2 billion in Southern wealth was tied up in the value of slaves.
Ultimately, it was the debate over slavery and its spread that caused the split. Northerners viewed slavery as either somewhat of a "peculiar institution," which had to be tolerated to keep the country together or (in the case of the likes of John Brown) as a sin against humanity that would require fire and the sword to eradicate from our nation. The South, whose population of about 10 million was 40 percent slave, viewed the institution as both sacred and indispensible.
The issue, then, was the foundation of secession and the Civil War, but its roots as a controversy can be traced back to the Missouri Compromise of 1820. The admission of the slave state, Missouri, and the free state, Maine, resulted in maintaining parity in the US Senate. Also, the compromise set the boundaries of slavery at the southern border of Missouri, which would hold until 1850 as the North continued to give ground on the issue of introducing slavery to new territories.
The North made further concessions in 1850 with the egregious Fugitive Slave Act, which put the resources of the Federal Government at the disposal of slave catchers chasing runaways into Northern states. With the sanction of law on their side, Southerners also were happy with the 1857 Dred Scott decision, where the Supreme Court refused to prohibit moving slaves into free states on the basis that slaves were "property" of the "owners" who took them there.
Three years before the infamous Dred Scott decision, the Northern Senator Stephen A. Douglas, in the name of compromise, helped sow additional angst and discontent on the this issue through his Kansas-Nebraska Act of 1854. Simply stated, the Act called for "popular sovereignty," where residents of a new territory could decide by ballot whether they wanted to be a free or slave state. What resulted was a disputed election in Kansas two years later that would be a prelude of the Civil War to come. So-called "Bleeding Kansas" - - where the likes of John Brown murdered in the name of abolition, or where pro-slavery "Bushwhackers" razed Laurence, Kansas - - would continue until the issue was resolved with the beginning of the real fighting back east.
Before the Kansas issue was resolved and about 15 months before the Civil War began, John Brown, accompanied by three of his sons and two dozen followers, took over the federal arsenal at Harper's Ferry, Virginia (now West Virginia). His crackpot plan was to lead an uprising of slaves, flee to mountains and launch attacks on Southern slave states. Bankrolled somewhat by rich Northern abolitionists, Brown was the embodiment of Southern paranoia over slave uprisings and growing suspicion of and alienation from their Northern countrymen.
None other than (then Colonel) Robert E. Lee led the US troops that smoked out, captured and imprisoned Brown and his followers. Typically, Northerners, in their deference to Southern sensibilities, allowed the State of Virginia to try, convict and hang John Brown. While walking to the scaffold John Brown gave a chilling premonition of the bloodletting that would be a metaphor for our country's civil war:
"I, John Brown, am now quite certain that the crimes of this guilty land will never be purged away but with blood." [1]
No one could possibly predict the cost in blood and destructiveness that would follow after the South seceded. In fact, not even rabid pro-Unionists would admit that the Civil War was even about slavery. In the end, though, our country's rebirth through the Civil War was a sort of baptism of blood that was bigger than mortal men could fathom. Lincoln, who was unusually prescient for his generation, said it best when he said words to the effect that "The Almighty had His own purposes."
Source for quote:
[1] West Virginia Archives and History, "John Brown and the Harper's Ferry Raid" (http://www.wvculture.org/History/jnobrown.html)