Senetor Sumner critizied pro slavery groups in Kansas and Brooks beat Sumner with a cane over it.
The Kansas- Nebraska Act made the people vote weather or not they were going to have slavery in Kansas and Nebraska. This act made antislavey northerners mad.
In Kansas and Nebraska they used popular soverntiey to decide if there would be slavery or not. To impact the elections people from other states would go to or move to Kansas to try to impact the election on way or the other.