History of North America

How did the Kansas-Nebraska act deal with spread of slavery?

The Kansas-Nebraska Act of 1854 created the territories of Kansas and Nebraska and left the decision of whether or not they would allow slavery up to the vote of their citizens, thus repealing the previous Missouri Compromise's prohibition of slavery north of the 36°30′ parallel. This provision became known as "popular sovereignty" but led to increased tensions and "Bleeding Kansas".