Answer:
It is used to describe a period of violence during the settling of Kansas territory between 1854 and 1861.
Step-by-step explanation:
In 1854 the Kansas-Nebraska Act overturned the Missouri Compromise Act that set the boundaries between free and slave territories.
The Kansas Act declared that the residents should decide whether the area became a free or a slave state by using the principle of popular sovereignty. Soon after that, a flood of proslavery and free state people arrive in Kansas to attempt to influence the citizen´s decision. The violence began eventually because of the confrontation of both sides.
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