How did bleeding kansas lead to the civil war?

"Bleeding Kansas" refers to the conflict over whether Kansas would enter the Union as a free or slave state. The Kansas-Nebraska Act of 1854 had declared the decision in Kansas would be determined by "popular sovereignty." Supporters of each side then flooded the territory (pro-slavery from Missouri, free-state abolitionists from the north), hoping to sway elections. Competing legislatures were set up (free-state in Topeka, pro-slavery in Lecompton), and the tensions and violence that broke out between the two, with no resolution or compromise apparent, foreshadowed the coming Civil War.