What are three causes that led to the civil war?

slavery, sectionalism and state's rights.

Explanation:

The Abolition Movement, The Election of Abraham Lincoln, and Economic and Social Differences

Explanation:

The Abolition Movement: The Northerners were against slavery and they began to fight against the system of slaves, becoming Sympathetic with them. They wanted to end slavery.

Election of Abraham Lincoln: The Southerners believed that Lincoln was against slavery and was biased towards the North. Therefore, seven of the states left the Union before Lincoln's presidency.

Economic and Social Differences: The Southerners mainly focused on slavery and farming lives, meanwhile the Northerners focused mainly on cities and the industrialization life.

a system of cooperative federalism emerged, as the powers of the federal government expanded.