Reason One

Economic and social differences
The north and south had economic and social differences. The north believed in manufacturing and large cities. The south believed in slavery and large plantations.

Reason Two

States vs Fetarel
The states feared there power geting taken away. As a result the southen states secessed.

Reason Three

Slave vs Nonslave states
The goverenment had a problem of desiding the new state should be slave or nonslave states. The compromise of 1850 helped the balanced the slave and nonslave states.