Final answer:
Key issues in the 19th-century debate over slavery and expansion in the U.S. included the Missouri Compromise, the Compromise of 1850, Texas Independence, the Wilmot Proviso, Bloody Kansas, the Dred Scott Decision, and the Fugitive Slave Act, each marked by intense struggle and resulting in significant historical impacts.
Step-by-step explanation:
The historical debates and legislative actions surrounding slavery and territorial expansion in 19th-century America were marked by a series of compromises and conflicts that represented the deepening division between the North and South. Central among these were the Missouri Compromise of 1820, the Compromise of 1850, the Texas Independence, the Wilmot Proviso, the violent conflict of Bloody Kansas, the impactful Dred Scott Decision, and the controversial Fugitive Slave Act. The Missouri Compromise addressed the issue of balancing slave and free states and banned slavery north of the 36°30' line, while the Compromise of 1850, orchestrated by Senator Stephen Douglas, aimed to reduce sectional tension by addressing the status of territories and improving the Fugitive Slave Act.
Texas Independence became a contentious issue due to the implications for the balance of power between free and slave states. The Wilmot Proviso, which intended to ban slavery in territories acquired from Mexico, was never passed but ignited fierce debate. Bloody Kansas was the result of competing pro-slavery and anti-slavery settlers trying to affect the status of Kansas as slave or free. The Dred Scott Decision by the Supreme Court declared that African Americans were not citizens and could not sue in federal court, also indicating that Congress had no authority to prohibit slavery in the territories. Finally, the Fugitive Slave Act required citizens to assist in the capture of escaped slaves and brought the issue of states' rights to the forefront as it clashed with the personal liberty laws passed in northern states.