The Kansas-Nebraska Act of 1854 is a significant event in Black history as it directly contributed to the tensions leading up to the Civil War. The act allowed the settlers of Kansas and Nebraska territories to decide for themselves whether they would allow slavery within their borders, a concept known as popular sovereignty.

This decision led to a violent struggle between pro-slavery and anti-slavery factions in Kansas, known as "Bleeding Kansas," as both sides sought to gain control of the territory. The conflict resulted in numerous casualties and highlighted the deep divisions over the issue of slavery in the United States.

For African Americans, the Kansas-Nebraska Act further heightened fears about the spread of slavery and the protection of their rights. Many abolitionists viewed the act as a betrayal of the principles of freedom and equality, and it galvanized their efforts to oppose the expansion of slavery into new territories.

Overall, the Kansas-Nebraska Act played a significant role in the lead-up to the Civil War and highlighted the growing tensions over slavery in the United States.