Memory Causes for the Civil WarVersión en línea Identify the causes that led to the American Civil War. por Andrew Balzer loyalty to one's own region or section of the country, rather than to the country as a whole Sectionalism Popular Sovereignty Kansas-Nebraska Act Fugitive Slave Law Novel written by Harriet Beecher Stowe that showed the horrors of slavery. California entered as a free state Let the people of the territories themselves decide whether slavery would be permitted. Uncle Tom's Cabin 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 It required that all escaped slaves, upon capture, be returned to their masters and that officials and citizens of free states had to cooperate.