Memory Causes for the Civil WarVersión en línea Identify the causes that led to the American Civil War. por Andrew Balzer Kansas-Nebraska Act Sectionalism Let the people of the territories themselves decide whether slavery would be permitted. Popular Sovereignty It required that all escaped slaves, upon capture, be returned to their masters and that officials and citizens of free states had to cooperate. California entered as a free state loyalty to one's own region or section of the country, rather than to the country as a whole Uncle Tom's Cabin Novel written by Harriet Beecher Stowe that showed the horrors of slavery. Fugitive Slave Law It allowed people in the territories of Kansas and Nebraska to decide for themselves whether or not to allow slavery within their borders. Compromise of 1850