What did the Kansas-Nebraska Act of 1854 allow settlers to do?

The Kansas-Nebraska Act of 1854 is significant in U.S. history because it introduced the concept of popular sovereignty. This allowed settlers in the newly created territories of Kansas and Nebraska to decide for themselves whether to permit slavery within their borders. This decision-making process was aimed at addressing the contentious issue of slavery's expansion into new territories and was thought to be a compromise that would ease tensions between pro-slavery and anti-slavery factions.

The Act effectively replaced the Missouri Compromise, which had established geographic boundaries for the expansion of slavery. By allowing settlers to vote on the issue, the Kansas-Nebraska Act heightened national tensions and contributed to conflict, notably leading to violence in Kansas known as "Bleeding Kansas." This illustrates the Act's critical role in the pre-Civil War landscape where territorial governance and the question of slavery were deeply intertwined.