1854
Kansas Territory, US
The Kansas-Nebraska Act of 1854 allowed settlers in Kansas and Nebraska territories to decide through 'popular sovereignty' whether to permit slavery, sparking violent conflict known as 'Bleeding Kansas'[6]. Pro-slavery 'Border Ruffians' from Missouri crossed into Kansas to intimidate anti-slavery settlers and vote illegally, leading to bloody fighting over slavery expansion in the Kansas Territory[6]. This conflict resulted in dozens of deaths and became a precursor to the Civil War, highlighting the violent resistance to halting slavery's expansion.
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