What was the war about? For many people today, slavery was the main reason why the Civil War happened. However, the cause of the Confederacy expressed in the secession declarations was not only about slavery but also about freedom and independence. Mimicking the Declaration of Independence of 1776, southern states used the right to revolution against an oppressive government in their favor. They claimed that they had entered into a confederation voluntarily and that each individual state had retained their sovereign rights and independence when they entered the country. Pointing to recent violations of their rights to take slaves into new territories, to have slave property protected and returned from the northern states, and the election of a sectional and abolitionists presidential candidate, the southern states, one by one declared they would reassume their status as independent countries and fight against foreign invadors. President Jefferson Davis emphasized during his term in office that all he wanted was for the southern states to be left alone and to their own affairs.

Irish migrants in the country claimed like Patrick Cleburne that the war was about independence, freedom, and an end of northern oppression and not slavery. Another Irish volunteer in Missouri claimed that the southern states had the same right to liberty that Ireland and Belgium had.