What are the main causes of the American Civil War?

The economies of the northern states were based on free farming and industrial production, in the southern states large landowners flourished, controlling huge corn, cotton and tobacco plantations on which slaves worked, while in the north, slavery was already abolished. The presence of slaves and the lack of modern agricultural implements made the economy of the southern states backward and archaic, which hindered the development of the entire country. The main reason is the struggle for power.