Why did the US Civil War begin?

As of 2002, 60,000 books had been written about the US Civil War. Additionally, there are 6,000 books on President Lincoln. The numbers just mentioned are 13 years old and there is no doubt that many more books have been written since then. Clearly among the number of books already mentioned, there is more than one historian who as expressed logical opinions on the "exact" cause of this painful war.
To say that slavery was the main cause of the US Civil War cannot be totally correct. There were other factors involved in this war.
The fact that in 1857, the US Supreme Court ruled that the institution of slavery was Constitutional removed at that time, that slavery caused the war. Before there were enough states to amend the Constitution, most historians believe this uneconomical and immoral institution would have no doubt simply gone out of existence.
Slavery existed in the British American colonies, the West Indies and in Brazil as example, for a long time. The need for it disappeared in the Northern states before the Declaration of Independence.
Because the number of slave holding states in 1860 were fifteen, the ability to pass a Constitutional amendment would have been impossible.
The US Civil War began because the key political and economic persons of the time could not reach a compromise on the issue of slavery. Slavery was just as immoral in 1860 as it was in 1840. What seems clear is that the cultural differences between the plantation oriented Southern aristocracy, and the Northern business bourgeoisie and the political leaders attached to both groups failed to have the vision that slavery would by economic necessity added to its immoral and unnatural condition in a democratic nation, dissolve.
Few rank and file soldiers on each side were not going to die on the issue of slavery. It can be said that once so many lives had been lost, the war reached a point of no return.
That is a weak position to take. That 300,000 troops had been killed did not mean that adding another 320,000 lives to the list of those already killed was the solution. The level of intelligence in the areas of political science and economics was certainly adequate to have prevented America's worst tragedy in its history.

The civil war began over slavery. the north thought it wasn't right for there to be slaves because they didn't need slaves up north.
so many reasons
im telling you breifly but you should read more bout it. its gk.

the northern and southern states had proceeded along different paths of development:north on the industrial base and south was agricultual.north wanted to make changes in transportation and communication for bennifit of industry. south thought this would affect the soils fertility.

north and south states clashed over tarrif(a kind of tax paid on goods coming into the country).

issue of slavery was a crucial point too. this is somewhat the main point.
slavery had existed in america long before the war of independence.north did not want slavery and gave up the idea but south needed slaves to work in the feilds.slaves were totured and treated like personal property of owners.

america grew in size, people migrated westwards.
the south wanted to continue slavery in the new states but north was against it.

so that was it. these are only the reasons i know and most people know. there might be others .
hope it helps.