How did the kansas nebraska act affect the spread of slavery?

The Kansas-Nebraska Act of 1854 allowed the territories of Kansas and Nebraska to decide for themselves whether to allow slavery through popular sovereignty. This led to violent conflict known as "Bleeding Kansas" as pro-slavery and anti-slavery settlers rushed into the territories to sway the vote. The act effectively repealed the Missouri Compromise, which had previously restricted the spread of slavery, thus intensifying sectional tensions and contributing to the rise of the Republican Party and the eventual Civil War.