What did the Kansas-Nebraska Act of 1854 allow the people in those territories to decide?

The Kansas-Nebraska Act of 1854 was significant as it introduced the concept of popular sovereignty, which meant that the residents of the Kansas and Nebraska territories would have the right to decide for themselves whether to allow slavery within their borders. This act effectively nullified the Missouri Compromise, which had previously established a line determining slave and free states, leading to heightened tensions between pro-slavery and anti-slavery factions.

The ability for citizens to choose the status of slavery in their territories was meant to resolve conflicts over slavery's expansion but instead led to violent confrontations, known as "Bleeding Kansas." This choice was pivotal in the broader struggle over slavery in the United States, making it a key element of the political climate leading up to the Civil War. The focus on whether to be a free or slave state highlights the central role that slavery played in America's national discourse during this period.