Why did the Southern states sussed from the Union?

Answer 1

The Revolutionary War established the notion that government is subservient to the people and when a government ceases to represent the will of the people, it is that people's duty to remove themselves from that government and establish their own. The Constitution of the United States established the related notion that "rights" do not derive from the government but from the consent of the governed. And, specifically, anything not enumerated in the Constitution is reserved to the States. That is the main issue of the 1860 War of Northern Aggression. Government in Washington D.C. no longer represented the interests of the Southern States. They, then, exercised their right to secede from the Union.

Answer 2

The Southern states seceded from the Union primarily due to their disagreements with the federal government over issues such as the expansion of slavery into new territories and states, states' rights, and economic differences. They believed that secession was necessary to protect their institution of slavery and preserve their way of life. Ultimately, the secession of the Southern states led to the American Civil War.