The Kansas Nebraska act lead to bleeding Kansas which is an event that sparked the tension for the civil war. The Kansas Nebraska act, 1854, splitted the Nebraska territory into two states. These two states governed themselves.
Stephen Douglas as a US senator mandated Popular sovereignty in these states. This meant that the states got to decide whether or not their state will be a free or a slave state. This went against the Missouri Compromise saying that anything above _____is free and below is Slave. Except Missouri which is a slave state. The congress made popular sovereignty in these states because they could not decide themselves. It got so difficult that the congress almost split I to two, but instead they handed the decision to the people.
At this time there were two different kinds of settlers. There were the pro-Slavery settlers which were later known as the southern Whigs. The southern Whigs then became the party known as the Democrats. They wanted slaves to use for the railroads that they where going to use the new land for. The other was anti-slavery settlers also known as northern Whigs. The northern Whigs became the Republican party later on. They didn't believe that slaves were moral.
It was a hard decision and brought much tension. These two groups of settlers, like congress did not come up with a decision to be free or slave. They started physically fighting in the streets about wether or not they should be free or a slave state. This is known as Bleeding Kansas.
In the photo above you see the northerners wanted to use this new land for farming, on the other hand the southerners wanted to use the land to become rich from making a railroad. But to build this train track the southerners needed their slaves. So they ask if there are slaves allowed. When this happened the northerners and the southerners righted about it and handed the decision to congress. As congress discussed about it they couldn't come to a verdict so they made popular sovereignty to give the settlers the power of the decision. In a result they start fighting again, because they couldn't decide.
